texts: Uploading overlapping contours into PostgreSQL?

texts:
I've got 100+ shapefiles of contours with the following fields:

class (text)

altitude (double)

geom (geometry)

And I need to upload them into a single table in PostgreSQL.

Now, I've managed to upload about 50 of them using QGIS and pgAdmin III. I'll upload them each as their own table using QGIS' DB Manager, and then using pgAdmin III I'll run an insert query to simply tag it onto the end.

The trouble is, the other 50 shapefiles overlap with other shapes I've uploaded. The ones already uploaded are fine - no overlaps - but the remaining 50 all need some amending so we're not doubling up on features. For instance, one shapefile may be directly next to another that's already been inserted, and the two slightly overlap.

I would imagine using an ST_Difference would do this but I'm having trouble with the syntax, as well as preserving the data. There is also some difficulty with the size of the data that's already in there (500,000+ records).

I should mention that the geometry in question is linestring.

Currently I think I'm looking at having to chop this all down manually, which will be pretty time-consuming, and was wondering if anyone would post an example of using ST_Difference with two tables in order to chop table A down so that it doesn't include anything from table B, but still preserve the class and altitude?

EDIT - Alternatively, if anyone knows how to make polygons out of linestrings/polylines (so essentially we get an "outline" of the shapefile coverage) that would be great, as I could just generate and clip on them locally. I did experiment with concave hull, will have to try that again. It always stopped at the end (currently using QGIS 2.18.13).


texts: Include value from list in PyQGIS selectByExpression command

texts:
I've been going through the cookbook to try to find a way to include a value from a list in a selection command and can't figure it out.

roadlist=[]
layer = iface.activeLayer()

for feature in layer.getFeatures():
    if feature['RoadMntnc'] not in roadlist:
        roadlist.append(feature['RoadMntnc'])

for road in roadlist:
    print (road)
    layer.selectByExpression('"RoadMntnc"= road', QgsVectorLayer.SetSelection)
    selection=layer.selectedFeatures()
    for feature in selection:
        print (feature['chainage'])

How should the following line be structured to include the value for road from roadlist?

layer.selectByExpression('"RoadMntnc"= road', QgsVectorLayer.SetSelection)

If I put in the name of a road as layer.selectByExpression('"RoadMntnc"= \'Main_Rd\'', QgsVectorLayer.SetSelection) it works fine but I need the iterative value from roadlist.


texts:
I have a shapefile (polylines) of some roads and I want to divide the roads in ramps.

Ramp = a piece of the road delimited by the top of a hill and a valley.

So, pretending that you're driving in these roads, when you're going up you have one polyline for this part of the path, when you start going down you have another polyline of this path.

I have the Digital Elevation Model of the area, which I made using the "Topo to Raster" tool from "Spatial Analyst". To make it I used the shapefile of the rivers (stream), the limit (boundary), the point elevation and the contour (10 meters)

I found a set of tools called ET Surface and what I need is exactly what the tool  "Split PolylineZ based on slope direction change" does, but I don't have the licence to use it.


texts: Use Field List from Input Feature Class as Parameter in ArcGIS ModelBuilder

texts:
I set up a model that shall use an attribute field from a given feature class as a parameter. The feature class is a model parameter by itself and I want the user to choose the feature class first and then one attribute field from the ones contained within this chosen feature class. The only working way right now is to type the correct field name, but what if the user does not know the name and just wants to choose from a list? This is my model with the input mask:

I want the "Dissolve Field" to be a list of all available attributes from the input polygons, but I get an empty dropdown, since I don't know how to tell the model to read all field names and parse them to the dropdown menu.

This is specifically for using the model builder, NOT for a python script, where I know that you can do stuff like this with the "Validation" tab in the properties.

Using field parameters in calculate field is not exactly what I'm looking for, if I got the question right.


texts: How do I display latitude longitude data on a UTM map?

texts:
I'm relatively new to GIS, so I may use incorrect terms, but I'll try my best.  I'm using ArcView 10.  My current coordinate system information is as follows.

I believe this is correct, as it is the default coordinate system in our environment.

I have a CSV file that includes information I'd like to display on a map alongside all the other GIS layers I have available.  The problem I'm having is that the information in the CSV file is in latitude and longitude.

I was able to "Add Data" to import the CSV file.  The problem I'm having is displaying the data visually.  Using the "Display XY Data" tool, I have the following settings.

When I click "OK", the data is plotted visually, but not where it should be.  I think it's treating the relatively small latitude and longitude values as whatever projection the map is using.  I can see the layer is displayed if I zoom out to 1:30,000,000, so I am successfully displaying the data, however it should be shown on top of the existing layers.

Is there a way to convert the latitude and longitude data from a CSV file on import to display correctly?

Update:  Here's a sample ofthe CSV data I'm working with.

WorkOrder  Lat           Lng
00001      46.51169347  -84.32934394
00002      46.51232708  -84.33508238
00003      46.50809868  -84.32696865
00004      46.50980299  -84.33103097
00005      46.51359957  -84.33543261


texts: QGIS python originalName() does not return actual original layer name

texts:
I am writing a Python QGIS Plugin, using QGIS version 2.6 as the basis for development. When loading data into the canvas programmatically, I am trying to maintain the spatialite table name as the original name of each layer, so I can reference it to call functions on the data from GUIs in QGIS. However, I notice that when using QgsMapLayerRegistry to get the layers, the .originalName() function does not return the original name. Instead, it updates with the current layer name.

I have tried loading the vector layer using iface.addVectorLayer with the table name as the layer name, and changing the layer name after it has been loaded to see if that would maintain the original name, but I still have no luck. My workaround is load the vector layer as described above, but then call the .id() to get the original layer name, but the string returned from id() appends a long datetime to the end of the layer name, which makes my scripting work more complicated since the datetime has to be stripped out.

Is there a reason that the .originalName() function does not return the original name of the layer?

To be clear, this is how I load the spatialite layer into the canvas:

table_name = <spatialite table name>
display_name = <name to show in table of contents>
layer = iface.addVectorLayer(uri.uri(), table_name, 'spatialite')
layer.setLayerName(display_name)

And when trying to get the original name of the layer:

for layer in QgsMapLayerRegistry.instance().mapLayers().values():
    print layer.originalName()

But the result from layer.originalName() just returns the display_name, not the table_name that the layer was initialized with.


texts: Converting MXD file to earlier version/release?

texts:
I upgraded from 10.0 to 10.1 for a few days.  Due to conflicts with other packages, i had to downgrade back to 10.0.  Now I cannot open any .mxd file I opened with 10.1.

I did not create any with 10.1, they were all 10.0 mxds that ArcGIS "upgraded" for me, so it's not an issue of unsupported features.

How can I "downgrade" the mxds?  10.0's MXD Doctor can't find any layeres in the MXDs opened and saved with 10.1.


texts: how do I create a RESTful PostGIS web Service Framework?

texts:
I have PostGIS tables that store vectors that want to show on Google Maps.
Read the post How to display a PostGIS table on Google maps? But one thing that was not clear to me how do I create a RESTful PostGIS web Service Framework for feed data? I have all my data published in GeoServer, I do with it?


texts: Install QGIS on Ubuntu using the compressed format qgis-2.8.3.tar.bz2

texts:
I just can't use apt install because slower internet connection and size of QGIS. Can you show me how to do install using qgis-2.8.3.tar.bz2 file?

I have tried decompressing and use the command ./configure which resulted in error there is no make file but the decompressed file has cmake file in it.

Is there a way to use the decompressed file to install QGIS?


texts: Viewing Google Earth Engine source code -- Landsat TOA

texts:
I am working on a project looking at satellite calibration, and would like to see how Google Earth Engine performs ee.Algorithms.Landsat.TOA(image). I know that they incorporate the metadata information and also Chander et al. (2009).I checked the Google Earth Engine API on Github, but couldn't find the details on how the metadata information is applied across the entire image. Specifically, it would be helpful to know:

Do they use the per-pixel sun/sensor angle, or use the center of scene sun angle available in the metadata?
How do they apply calibration across an image? Would it be similar to how spectral indices are calculated image.select('band#')?


texts: Accumulate selections by expression using a for loop (Pyqgis)

texts:
I need to run a for loop to select features by their attributes, because the values are within lists (strkey and strvalue). I'm using the following script:

k=0
v=0
layer = iface.activeLayer()
for item in keys:
    listk = strkey[k]
    listv = strvalue[v]
    layer.selectByExpression('\"LINE_ID\" IN ('+listk+') AND \"Declividad\" IN ('+listv+')', QgsVectorLayer.SetSelection)
    v=v+1
    k=k+1

The problem is that only the last feature is selected. Is like every loop the Qgis erases the old selection to select the new feature.
Is there a way to accumulate the selections ?


texts: Opening File Geodatabase in QGIS for Ubuntu?

texts:
So far I have found instructions on stack exchange but they are for windows. And so far the information I have found is for windows. I currently have Ubuntu 13.04 Raring tail.  I am using qgis 1.8. I understand that gdal automatically comes with it and I should be able to open it(.gdb). I have the .gdb file on my computer.  I have tried add vector layer and source type as file and Database and directory. The option for database wants to me connect to a server but I don't need to.

Installing File Geodatabase (*.gdb) support in QGIS?

Open Source Tool capable of reading Esri File Geodatabase (.gdb)?

I tried to install ubuntu gis ppa, the stable and unstable version, this actually caused qgis to lost the python plugin option and I have to do a clean uninstall. sudo apt-get remove --purge qgis

https://launchpad.net/~ubuntugis/+archive/ubuntugis-unstable

I did read this on stackexchange:
Migrating geodatabase data into PostGIS without Esri apps?

This maybe my answer but does he mean put that in the terminal?


texts: qgis2 - hide a layer (or its labels) when another layer is coincident?

texts:
I have two road layers - one is a subset of the other, so, there's a lot of overlap.  When they are coincident, I see labels from both layers.

The 'lower' layer is the thin line road in the SW corner; the 'upper' layer is the thicker line road with black edges.

One of the 'Ridge Rd' labels is from the upper layer, one is from the lower layer.  Ultimately I'd like to get rid of this resulting 'double label' effect.

Is there a way to suppress labels from the lower layer when it is coincident with an object from the upper layer?  Is the best way to do this by keeping them on the same single layer and just do a rule-based or categorized style, to avoid this whole multi-layer issue?  That would have other side-effects though I haven't explored the option yet.

Thanks in advance


texts: Removing elements that cut other elements using QGIS

texts:
I have line elements and polgone-elements on two different layers (lets say layer A (line) and layer B (polygons). Now I want to remove all elements of layer A that crosses/touches/laying in polygones of layer B.

I tried the "difference"-function but this function only removes the part of the line laying in the polygon (and I want to remove the whole line).


texts: arcpy.env.overwriteOutput() not working with arcpy.FeatureClassToShapefile_conversion()?

texts:
I have created a simple model to transfer multiple feature classes to a shapefile. With the model I exported a .py script which I'd like to run with my task manager to update any changes each day.
The script that runs with out overwriting:

# Import arcpy module
import arcpy

# Local variables:
adverse = "F:\\Atco_gis\\temp_shapefiles\\LP_Layers_Temp.gdb\\adverse"
comments = "F:\\Atco_gis\\temp_shapefiles\\LP_Layers_Temp.gdb\\comments"
desig_crossing = "F:\\Atco_gis\\temp_shapefiles\\LP_Layers_Temp.gdb\\desig_crossing"
Temp_LP_Layers = "F:\\Atco_gis\\temp_shapefiles\\Temp_LP_Layers"
Temp_LP_Layers__2_ = Temp_LP_Layers

# Process: Feature Class To Shapefile (multiple)
arcpy.FeatureClassToShapefile_conversion("F:\\Atco_gis\\temp_shapefiles\\LP_Layers_Temp.gdb\\adverse;F:\\Atco_gis\\temp_shapefiles\\LP_Layers_Temp.gdb\\comments;F:\\Atco_gis\\temp_shapefiles\\LP_Layers_Temp.gdb\\desig_crossing", Temp_LP_Layers)

I have been reading that:

arcpy.env.overwriteOutput = True

should solve the problem however it leaves me with a new output with _1 or _2 depending how many times the script has been ran.

Any suggestions?


texts: arcpy: Select layer by attribute with SWITCH_SELECTION seems not to work

texts:
I have a large feature classes, where a field named "gridcode" contains integers values from 6 to 17. I would like to get rid of features, where the gridcode = 6, 9 or 15.

Therefore, I have created a query where gridcode = 6 OR gridcode = 9 OR gridcode = 15.

Further, I wanted to apply tool Select layer by Attribute and switch my selection, i.e. end up only with field "gridcode" does not contain neither 6, 9 or 15. I wanted to apply this tool, as it takes "SWITCH_SELECTION" argument.

I have save up my selection, just to verify if the process was accurate. And it seems that the selection or the dropping of my variables did not occur.

Could there be a problem with my coding?

How otherwise I can drop my rows by attribute?

My code:

# Import modules
import arcpy, os
import itertools

# Allow files to overwrite
arcpy.env.overwriteOutput = True

# Set working environment
inWD = "C:/Projects/2018_deforestData"
arcpy.env.workspace = os.path.join(inWD, "input.gdb")

# Define outPath
outPath = os.path.join(inWD, "output.gdb")

# Define input variables
inSAO = "AllSAO"

# create clauses
field = "gridcode"

# Select correct years from SAO

# Create attribute query for SAO data:
# drop years yearsSAO = [6, 9, 15]
# Create layers and apply atribute query
querySAOall = field + "=" + str(6) + " OR " + field + "=" + str(9) + " OR " + field + "=" + str(15)

# Make feature layer from my input data
arcpy.MakeFeatureLayer_management(inSAO, "SAOLayerAll")

# Select by attribute and switch the selection
arcpy.SelectLayerByAttribute_management ("SAOLayerAll", "SWITCH_SELECTION", querySAOall)

# Save file to make sure the correct years are used
outSAOcorrectYears = os.path.join(outPath, "SAO_correctYears")
arcpy.CopyFeatures_management("SAOLayerAll", outSAOcorrectYears)


texts: I'm using a tool in QGIS where I'm creating points in a grid and I am specifying the points to be created every 0.5 of the user-defined atlas size. In other words, 0.5 map units of the CRS. What is the map unit of WGS 84? Is it km or m or degrees?


texts: Draw linestring programmatically using draw control

texts:
I want to draw linestring feature programmatically which can be done from draw control of openlayers which can inherit default behavior of draw control that is modification, selection, undo, redo etc

I found one method in openlayers but seems not working for me

drawControls.line.drawFeature(geometry)


texts:
I have my own routing server that uses OSRM as an routing engine. (I used this toturial.)

I want to be able to add my own data (roads) and include that data in the routing.

So in the beginning I thought to add my data in the OSM format (node, way, relation) with an id that doesn't exist in the xml file to the osm.xml file that the OSRM uses to route. But that will mess up the id's coming from the OSM server in case of updating the data (diff).

So now I'm wordering if there is any way to use OSRM with my own data.


texts: QGIS Temporal Controller with raster data

texts:
Starting from QGIS 3.14 TimeManager is dead, long live the Temporal Controller!
There are a lot of tutorials out there how "Temporal Controller" deals with vector layers, which looks nice. However, I'm working a lot with raster data and I cannot find any information, how to get a similar behaviour as it was in TimeManager.
I have a NetCDF like this:
ncdump -h SLA_ts.nc
netcdf SLA_ts {
dimensions:
    time = 124 ;
    lat = 5 ;
    lon = 5 ;
variables:
    char crs ;
        crs:grid_mapping_name = "latitude_longitude" ;
        crs:long_name = "CRS definition" ;
        crs:semi_major_axis = 6378136.3 ;
        crs:inverse_flattening = 298.257 ;
    float time(time) ;
        time:long_name = "time" ;
        time:calendar = "standard" ;
        time:units = "days since 1858-11-17 00:00:00.0" ;
        time:actual_range = 52244., 55987.735625 ;
    float lat(lat) ;
        lat:standard_name = "latitude" ;
        lat:long_name = "latitude" ;
        lat:units = "degrees_north" ;
        lat:actual_range = 53.8, 54.2 ;
    float lon(lon) ;
        lon:standard_name = "longitude" ;
        lon:long_name = "longitude" ;
        lon:units = "degrees_east" ;
        lon:actual_range = 7.5, 7.9 ;
    float sla(time, lat, lon) ;
        sla:_FillValue = NaNf ;
        sla:grid_mapping = "crs" ;
        sla:long_name = "sea level anomaly" ;
        sla:unit = "m" ;

// global attributes:
        :Conventions = "CF-1.5" ;
}

When I load this file in QGIS, the time steps are loaded as bands (in the Symbology-Tab, they are displayed as Band 1: time=52244 (days since 1858-11-17 00:00:00) and so on...). However, the Temporal-Tab offers only a fixed time range as shown in the screenshot:
I would expect that the Temporal Controller automatically recognizes that the layers are time steps but the button "Automatic" is inactive. Has anyone any experience with raster layers in "Temporal Controller"? How can I modify my data to be interpreted correctly? Or is this functionality simply not implemented (as the Temporal Controller is quite new)?


texts: Buffer with unknown distance by adding numerical values of a column until a maximum

texts:
In my QGIS project, I have a vector of polygons representing slope zones around an archaeological site and I want to calculate the area which is necessary to supply the ancient population with a specific resource.

The slope vector incorporates the potential yield of this resource per feature. I have the total number of yield and I want to sum up the values of every feature from a point in the center of the site until it reaches that maximum.

Now I am looking for a possible way to create this extraction zone and I think in using a buffer. I noticed that there are only tutorials for buffers with fixed distances, but I couldn't find a solution with that.

In my opinion the best thing would be an expression consisting of the buffer and a condition instead of the distance. Unfortunately, I haven't much experience yet and have no idea how to do this.


texts:
I am trying to perform an intersection between two layers:

Polyline layer representing some roads (~5500 rows)
Polygon layer representing irregularly shaped buffers around various points of interest (~47,000 rows)

Ultimately, what I'm trying to do is to clip the polylines to these many (sometimes overlapping) buffers, and then sum up the total length of roadway contained within each buffer.

The problem is that things are running SLOW. I'm not sure how long this should take, but I just aborted my query after > 34 hours. I'm hoping that someone can either point out where I've made some mistake with my SQL query, or can point me to a better way of doing this.

CREATE TABLE clip_roads AS

SELECT
  ST_Intersection(b.the_geom, z.the_geom) AS clip_geom,
  b.*

FROM
  public."roads" b,
  public."buffer1KM" z

WHERE ST_Intersects(b.the_geom, z.the_geom);

CREATE INDEX "clip_roads_clip_geom_gist"
  ON "clip_roads"
  USING gist
  (clip_geom);

CREATE TABLE buffer1km_join AS

SELECT
  z.name, z.the_geom,
  sum(ST_Length(b.clip_geom)) AS sum_length_m

FROM
  public."clip_roads" b,
  public."buffer1KM" z

WHERE
  ST_Contains(z.the_geom, b.the_geom)

GROUP BY z.name, z.the_geom;

I do have a GiST index created for the original roads table, and (just to be safe?) create an index before doing the second table creation.

The query plan from PGAdmin III looks like this, though I'm afraid I don't have much skill in interpreting it:

"Nested Loop  (cost=0.00..29169.98 rows=35129 width=49364)"
"  Output: st_intersection(b.the_geom, z.the_geom), b.gid, b.geo_id, b.address_l, b.address_r, b.lf_name, b.lfn_id, b.lfn_name, b.lfn_type_c, b.lfn_type_d, b.lfn_dir_co, b.lfn_dir_de, b.lfn_desc, b.oe_flag_l, b.oe_flag_r, b.fcode_desc, b.fcode, b.fnode, b.tnode, b.metrd_num, b.lo_num_l, b.lo_n_suf_l, b.hi_num_l, b.hi_n_suf_l, b.lo_num_r, b.lo_n_suf_r, b.hi_num_r, b.hi_n_suf_r, b.juris_code, b.dir_code, b.dir_code_d, b.cp_type, b.length, b.the_geom"
"  Join Filter: _st_intersects(b.the_geom, z.the_geom)"
"  ->  Seq Scan on public."roads" b  (cost=0.00..306.72 rows=5472 width=918)"
"        Output: b.gid, b.geo_id, b.address_l, b.address_r, b.lf_name, b.lfn_id, b.lfn_name, b.lfn_type_c, b.lfn_type_d, b.lfn_dir_co, b.lfn_dir_de, b.lfn_desc, b.oe_flag_l, b.oe_flag_r, b.fcode_desc, b.fcode, b.fnode, b.tnode, b.metrd_num, b.lo_num_l, b.lo_n_suf_l, b.hi_num_l, b.hi_n_suf_l, b.lo_num_r, b.lo_n_suf_r, b.hi_num_r, b.hi_n_suf_r, b.juris_code, b.dir_code, b.dir_code_d, b.cp_type, b.length, b.the_geom"
"  ->  Index Scan using "buffer1KM_index_the_geom" on public."buffer1KM" z  (cost=0.00..3.41 rows=1 width=48446)"
"        Output: z.gid, z.objectid, z.facilityid, z.name, z.frombreak, z.tobreak, z.postal_cod, z.pc_area, z.ct_id, z.da_id, z.taz_id, z.edge_poly, z.cchs_0708, z.tts_06, z.the_geom"
"        Index Cond: (b.the_geom && z.the_geom)"

Is this operation just doomed to run for several days? I'm currently running this on PostGIS for Windows, but I could in theory throw more hardware at the problem by putting it up on Amazon EC2. However, I see that the query is only using one core at a time (is there a way to make it use more?).


texts: How to auto fill or delete sliver polygons without losing precision?

texts:
I am developing some boundaries in which precision holds the key value.

Using ArcGIS 9.3 I am converting lines to polygons using the "feature to polygon" tool.  The lines are accurate but I find gaps in between polygons.

Using GT [=ET?] wizard tools I made slivers and then eliminated them.

However, the problem persists:

some gaps still remains
I lose precision.

As I have a huge number of polygons, solving them manually will take ages & I am running short of time.

Can anyone help me resolving the 2 issues I mentioned, please?

I have no knowledge of programming but I can work in either ArcGIS or Quantum GIS.

Thanks in advance.


texts: Leaflet/GeoJSON - Changing the default blue marker to other .png files

texts:
How can I use different .png files to symbolize my GeoJSON data?
I have one property in my GeoJSON file that I would like to symbolize the data by (feature.properties.issue). For each different issue type, I would like to display a different .png file as a clickable marker.

Here is what I have so far. I'm very new to Leaflet/HTML/GeoJSON.
I can get each default marker to have a click-able popup that reads the GeoJSON properties ([Imgur pic of output here][1]), but I do not know how to change the symbology from the default blue marker.
You can see that I have two other .png files in the directory called "warningicon" and "testicon.png", but I'm unsure of where to put it in my code, or how to use a conditional statement in this instance to differentiate based on issue type.

var warningicon = {
    iconUrl: 'warningicon.png',
    iconsize: [32,32],
};

var testicon = {
    iconUrl: 'testicon.png',
    iconsize: [32,32],
};

$.getJSON("./geojson/sidewalks.geojson", function(data) {
    var geojson = L.geoJson(data, {
        onEachFeature: action_To_Perform_When_Marker_Is_Clicked_On_The_Map
    });
    geojson.addTo(map);
    myGeoJSONLayers.addLayer(geojson);
});

var overlayMaps = {"Sidewalk Issues": myGeoJSONLayers};

L.control.layers(baseMaps, overlayMaps,myGeoJSONLayers).addTo(map);

function action_To_Perform_When_Marker_Is_Clicked_On_The_Map(feature, layer) {
    if (feature.properties) {
        var PopupText = [];
        PopupText.push("Accessibility Issue: " + feature.properties.Issue);
        PopupText.push("\nDescription: " + feature.properties.Description);
        PopupText.push("\nRecorded: " + feature.properties.CreationDate);
        layer.bindPopup("\n" + PopupText.join("") + "\n");
    }
}


texts: Installing QGIS Statist plugin in Mac OS X?

texts:
I'm trying to install the Statist plugin.  I'm running MacOSX 10.7.5. with Python 2.7.3. and Numpy 1.5.1.

I have also installed matplotlib 1.1.0 (for python 2.7).  When I try to install the Statist 1.0.0 plugin, I get an error message saying that I need matplotlib installed. Somehow QGIS is not finding it.


texts: Installing Python plus ArcMap plus ArcGIS Pro plus GDAL?

texts:
My various installations of ArcMap, OSGeo4W and Python 2.7 (plus 3.4) are a mess. I've resorted to copying the entire Gdal directory (per version and processor) to the site-packages directory of all the Python installations (and things generally work) but this seems wrong. So I'm asking anyone with experience to help me out with a good installation. Here's what I've done:

Installed Python 2.7 (64-bit) to C:\Python
Installed Python 2.7 (32-bit) to C:\Pythonx86
Installed ArcMap 10.5 without Python
Installed ArcMap's Background Processing which automatically installs Python 2.7 into the ArcGISx64 directory
Installed OSGeo4W64 to C:\Program Files
Installed OSGeo4W to C:\Program Files (x86)
Installed ArcGIS Pro 1.4 which automatically installs Python 3.4

The biggest problem, of course, is that Python (and all the mods) gets deleted whenever I'm forced to reinstall ArcGIS (which happens way too often, unfortunately). Another problem is that sometimes Gdal returns an error when I import it in a script. Another problem is that the IDLE shell almost randomly switches between 32- and 64-bit versions even when clicking on the same shortcut.

Well, basically what I want is detailed help with the proper installation of these programs (and no, I don't want to switch to QGIS :))


texts: QGIS transformation local coordinate system to UTM35

texts:
I am creating a geo database for an archaeological excavation. We want to put data from a local system and from UTM35 in the same QGIS-project. I have Ground Control Points and I calculated transformation parameters with it. Translation of the X- and Y-Axis, Scale factor and Rotation angle (4 parameters 2D Helmert Transformation). The parameters can transform from the local system to UTM.
scale factor: 0.99960
rotation angle: 1.3002 degrees
Translation East : 522372.842 m
Translation North: 4151845.829 m

I setted the project to UTM35(EPSG 32635) and now want to create a custom coordinate reference system so that every layer in the local system could be converted on the fly to UTM35.
How can I do that?


texts: Error when clipping a raster and saving it to a gdb other than the Default.gdb

texts:
I have several large Raster-Datasets stored in a Geodatabase (Example.gdb). I created polygon-shapefiles to clip the Rasters to the extend which I actually need. This works fine, as long as I save the output to the Default.gdb, whenever I want to save it to the other GDB (Example.gdb) I get an Error. Also I get an Error when I try to import the new Raster-Datasets from Default.gdb into Example.gdb.

Obviously I want to keep all the Data for this Projekt in one GDB.


texts: Mapquest 'community license' service discontinuation terms?

texts:
I want to use MapQuest's geocoding services under their Community License: http://developer.mapquest.com/web/info/terms-of-use

I can't find the clause that explains under what terms I can discontinue using their service (and ofcourse, unsubscribe to their license).

Can I choose to terminate using their service at any time and will their license no longer apply to the app?


texts: The geotoolkit.org web site has very little documentation. From this document I get the impression that it is a fork from geotools; is that right? If so, what were the motives/objectives of the fork?


texts: Issue viewing OS OnDemand layers at certain scale ranges?

texts:
I am having some difficulties viewing OS OnDemand WMS layers at certain Scales.
For example, I have loaded the OS MiniScale layer which should be view-able between 1:236250 and 1:944928. However, if I attempt to view it at 1:500000 scale (with magnifier set to 100%), it doesn't render and I get the following error in the Log Messages Panel:

  Map request error (Status: 200; Response:

              xmlns:ogc="http://www.opengis.net/ogc"
              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xsi:schemaLocation="http://www.opengis.net/ogc http://schemas.opengis.net/wms/1.3.0/exceptions_1_3_0.xsd">

                   No requested layers (MS) are visible at the requested scale (189025)

              ; Content-Type: text/xml;charset=ISO-8859-1; URL:http://osondemand.ordnancesurvey.co.uk:80/ondemand/wms/MAP.do?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&BBOX=366531.5586588375154,617562.0833002466243,439270.4167577226181,682437.9166997533757&CRS=EPSG:27700&WIDTH=1375&HEIGHT=1226&LAYERS=MS&STYLES=&FORMAT=image/png&DPI=240&MAP_RESOLUTION=240&FORMAT_OPTIONS=dpi:240&TRANSPARENT=TRUE)

The confusing bit is, the scale in the Error Message does not correspond to the scale I'm trying to view it in QGIS. I've attached a screenshot to show the behaviour.


texts: Moving a group in QGIS into another group

texts:
I have an existing group in QGIS which I want to move inside another existing group. More specifically, I am trying to write a function which takes a list of group names, and nests each one under the previous. ie:

moveGroups(['group1', 'group2', 'group3])

would result in:

group1
>group2
>>group2

This is what I have so far but it just puts everything at the same level

def moveGroups(groupList):

    qgisGroupsRoot = QgsProject.instance().layerTreeRoot()

    for groupName in groupList:

        if groupList.index(groupName) == 0:
            continue

        if qgisGroupsRoot.findGroup(groupName):
            group_node = qgisGroupsRoot.findGroup(groupName)
            group_node_clone = group_node.clone()

            parentGroupName = groupList[groupList.index(groupName)-1]

            parentGroupIndex = iface.legendInterface().groups().index(parentGroupName)
            qgisGroupsRoot.insertChildNode(parentGroupIndex, group_node_clone)


texts: i have a dataset which contain object_id, poi_x and poi_y and another data set with same object_ids but different poi_x and poi_y. i want to join poi_x and poi_y from second dataset to first dataset. but failed to join. please any one tell me why it happens.


texts: Why the strange area calculation in QGIS?

texts:
I have a 550 meter by 550 meter square polygon in a shapefile.  The QGIS 2.18 project and the shapefile both reference EPGS:32648 WGS84/UTM48N. EPGS:32648 uses meters as the units. When I use $area to calculate the area of the polygon it populates the field with 75.74. This value is 302,500 square meters in acres.

Why is this field being populated with acres?


texts:
I've built out a model but it takes what feels like a very long time to run. About 60 seconds for each iteration and I only have 200 records. I am not sure what is normal or expected for these types of things? No tool in particular is drastically slower than the others, it's just all slow. I also feel like just a couple days ago virtually identical model was running much faster. It gets slower every day.

Does anyone have guidance on how to improve processing speed or are there other things in the background aside from the model itself that drastically slow this done? Looking to do anything I reasonably can to speed this up.

I've even tried coding some of it in ArcPy just using the same tools, testing out what might work. It ran even slower.

Attached is an image of the ModelBuilder and here is a list of the tools:

1) Active: Point Feature Class, approx 200 records

2) Iterates through each point

3) Pairwise Intersection to Identify the corresponding Parcel Record

4) Buffer .5 Mile Out

5) Intersect with Roads and School Zone polygon

6) Select which polygon layer the Selected Feature does not exist in (invert selection)

7) Delete the other polygons

8) Clip all other parcels that fall within our remaining polygon

9) Finish

In a nutshell identifying all parcels around a subject parcel that are within the same school zone and do not cross particular highways.


texts: How much permgen space should i add for using 5 geoserver

texts: My computer is windows 7 64 bit with 4 gb ram.  I am using 5 geoserver in a single apache.  How much amount of space i should added..


texts:
I am using PostGIS with geoserver. I have been able to publish a shapefile.zip as a layer.

The problem is, even though there is a .prj in the zip file, the Declared SRS in Geoserver is EPSG:404000

I would like to change it to EPSG:4326 using rest. The things I found, mention the xml to be used, but not how to implement it.

I get a 'Method is not allowed' error.

Here is the code I am using for doing it.

Dim gUrl As String = ("http://localhost:8080/geoserver/rest/workspaces/" & workspace & "/datastores/" & ds & "/featuretypes/alignment")

            Dim request As WebRequest = WebRequest.Create(gUrl)
            request.ContentType = "text/xml"
            request.Method = "PUT"
            request.Credentials = New NetworkCredential("admin", "geoserver")
            Dim buffer() As Byte = Encoding.GetEncoding("UTF-8").GetBytes("<featureType><srs>EPSG:4326</srs><projectionPolicy>FORCE_DECLARED</projectionPolicy></featureType>")
            Dim requestStream As Stream = request.GetRequestStream
            requestStream.Write(buffer, 0, buffer.Length)
            requestStream.Close()
            Dim response As WebResponse = request.GetResponse
            Return True


texts: Memory allocation error encountered when automating gridmetrics in R

texts:
I am trying to run Fusion's GridMetrics from R, I wrote this for one las file:

#First set up directories to keep the raw data
#separate from that produced by the analysis, Input (.las) and (.dtm),
#and output (.csv) directory in a dropbox folder.
mainDir <- "F:/Dropbox/LiDAR_Prj"
inDir <- "inputDirectory"
outDir<- "outputDirectory"
dir.create(file.path(mainDir, outDir), showWarnings = FALSE)
#Run grid metrics in FUSION
#Read in the .las files and use FUSION to produce the .csv files with values for 14 m pixel.

system(paste(file.path("C:","Fusion", "gridmetrics.exe"),
"/outlier:-5,250 /minht:1.64 /strata:8.2,16.40",
file.path(mainDir, inDir, "*.dtm"), 13.1,45.93,
file.path(mainDir, outDir, "2H8546.csv"),
file.path(mainDir, inDir, "2H8546.las"),
sep=" "))

It worked very well. However, I would like to automate it because I have more than 400 tiles to process (file names are not a sequence).

I attempted to use a txt file listing the data files instead of the file names:

mainDir <- "F:/Dropbox/LiDAR_Prj"
inDir <- "inputDirectory"
outDir<- "outputDirectory"
dir.create(file.path(mainDir, outDir), showWarnings = FALSE)

#Run grid metrics in FUSION
#Read in the .las files and use FUSION to produce the .csv files with values for 14 m pixel.
system(paste(file.path("C:","Fusion", "gridmetrics.exe"),
"/outlier:-5,250 /minht:1.64 /strata:8.2,16.40",
file.path(mainDir, inDir, "*.dtm"), 13.1,45.93,
file.path(mainDir, outDir, "halistcsv.txt"),
file.path(mainDir, inDir, "halist.txt"),
sep=" "))

but a warning message pops up:

Too many points (couldn't allocate memory for point list)...no metrics computed
Run finished: Tue Nov 22 19:39:35 2016 (elapsed time: 21 seconds)
***There were errors during the run
Done
Warning message:
running command 'C:/Fusion/gridmetrics.exe ... halist.txt' had status 5

Could any of you help me to figure out an efficient way to automate this process?


texts: Getting fid attribute and field name in ArcObjects and c#?

texts:
I am new to ArcObjects

In above attribute table I write query to select "0" in all fields. After I get cursor for looping  selected features.but my problem is I want show the FID number and field name which contain "0" attribute values as a message.

for example I want output like:

( fid ,field name

10,NAME

30,NAME

30,FIRST_CONT.........

)

here mycode

    ESRI.ArcGIS.ArcMapUI.IMxDocument mxd = ArcMap.Application.Document as ESRI.ArcGIS.ArcMapUI.IMxDocument;
    ESRI.ArcGIS.Carto.IMap map = mxd.FocusMap;
    ESRI.ArcGIS.Geodatabase.IWorkspaceFactory wsf= new ESRI.ArcGIS.DataSourcesFile.ShapefileWorkspaceFactory();
    ESRI.ArcGIS.Geodatabase.IWorkspace ws= wsf.OpenFromFile(@"D:\ARC OBJECTS", ArcMap.Application.hWnd);
    ESRI.ArcGIS.Geodatabase.IFeatureWorkspace fws = ws as ESRI.ArcGIS.Geodatabase.IFeatureWorkspace;
    ESRI.ArcGIS.Geodatabase.IFeatureClass fcls = fws.OpenFeatureClass("Find_null");
    ESRI.ArcGIS.Geodatabase.IQueryFilter qf = new ESRI.ArcGIS.Geodatabase.QueryFilterClass();
    qf.WhereClause = "FID_1 = 0 OR NAME = '0' OR POPULATION =  0 OR FIRST_CONT = '0'";
    ESRI.ArcGIS.Geodatabase.IFeatureCursor fcur = fcls.Search(qf, true);
    ESRI.ArcGIS.Geodatabase.ICursor cur=fcur as
    ESRI.ArcGIS.Geodatabase.ICursor;

    ESRI.ArcGIS.Geodatabase.IRow row= cur.NextRow();
    while (row!=null)
    {
      row= cur.NextRow();
    }


texts: Enabling File Geodatabase support in QGIS on OSX?

texts:
What steps do I need to take to get Esri .gdb files functioning in QGIS?

I'm a QGIS user running v2.0 (Dufour) on Mac OSx 10.8.5.  I have some data in .gdb format and need to access this and work with it in QGIS.  I'm a relatively savvy computer user, but not at all a programmer or developer.  I've been reading the forums and have seen some steps outlined for GDAL installs etc., and compiling etc., but am a bit daunted and don't want to mess something up on my system.

Alternately I could try to use GDB Flee or something like it, but not sure where to start.


texts: Where can I find documentation on the tool Relief Segmentation of the library Terrain Analysis?


texts:
newbie here of QGIS here, I was trying to aggregate a feature from a CSV with no geometries. The query is very basic:

SELECT
    "PROV",
    SUM("POP_2012") AS POP_2012
FROM "municipalities-tuscany"
GROUP BY "PROV"

but I'm stuck and cannot make it work: if I go to Data Source Manager > Virtual Layer, fill the form and set Unique identifier column equal to PROV the resulting layer shows only 1 instance (instead of 10), like I filtered it. If I try using DB Manager > Virtual Layers and open the SQL Window, I run and correctly visualize the query, but when I try to Load as new layer, set Column with unique values equal to PROV and click Load nothing happens. If I set no Column with unique values get nothing in both cases.


texts: Find spatially identical records in Mapinfo

texts: Is there a tool/mbx similar to the Arc INFO "Find Identical" to find records which have exactly the same shape?


texts: Transforming polygones with 90 degree edges by deleting the vertices

texts:
I have a lot of polygons of buildings with small balkonies and edges and zig-zags (see the figure below):

.

I want to delete vertices which does not satisfy a criterion like distance between vertices bigger than 3 meters.

Is there any script or tool for doing that?

I am familiar with writing python codes but I don't know how  can I write a script in QGIS. How can I find the names of variables, etc.?

Is there any tutorial for doing it in QGIS?


texts: Join Points Layer to a Polygon Layer Grouped by Field - ArcMap

texts:
I want to join a points layer to a polygon layer and summarize the points that fall within each polygon layer by a similar attribute in one of the point layers field...

For example I have hundreds of points that have a 'count' field of a certain amount of visits to a gym and there is also a field that specifies if they are a 'member', 'guest', or 'punchcard holder' ('CustomerType'). I want to join all of the points to a polygon geography layer (census block group) and summarize the points layer grouped by that 'CustomerType' field. I want my final output to be the polygon layer and each feature have the number of 'punchcard holder', 'guest', 'member', etc. and a sum of the visit 'count' from all the points.

I've been able to join the points layer to polygon layer and get the total number of visits by a spatial join but not grouped by'customertype'.


texts: Why aren't the info windows showing up on my cartodb layers?

texts:
I made a cartodb map with 2 layers. The layers draw from the same table but I use filters to display some of the data in one layer and some of the data in another.  Without the layers my info windows were working and now they're not.  I'm not sure how to start troubleshooting this.

The SQL expression on layer 1 is SELECT * FROM table_name WHERE useful_column > 0 and on layer 2 it is  SELECT * FROM table_name WHERE useful_column IS NULL -- the goal is to use a different info window altogether on the regions where useful_column has no data.


texts: How to convert WGS84 to UTM when the study area covers two zones: UTM 51N and 52N

texts: I want to use ArcMap to convert the WGS84 to UTM. But the study area covers two zones: UTM 51N and 52N. Which zone should I choose to output the result?


texts: Solving the problem with the "Indexing data" window while editing

texts:
When trying to edit a vector layer using node tool, I get constantly the next message:

Normally it appears once at the beginning of the edition and then it doesn't show any more, but now I get it constantly. It blinks very fast and I can't even edit the line.

I've tried to save this layer again as another shapefile. I have closed and re-opened the software. I have disabled all the plugins (just in case it's a matter of memory or rendering). None of this tries solved anything.

It is not the only layer where this happen, so I think the problem is not a corrupted file (or maybe everything is corrupted).

Anybody knows why this is happening and how to solve it?

(QGIS 2.8.6 on Windows 7)


texts: Postgres/PostGIS calculate area of Polygon in Square Miles

texts:
Polygon in Postgres/PostGIS database. It has the spatial reference 4269 which is in degrees.

I know there is a ST_Area() to calculate it.
this is my query to select the areas in the SRID units.

select st_area(geom) from counties;

I want to calculate the area in Square Miles and insert a column named Area with the correct Square Mileage for each county

*I am a new to SQL and Postgres


texts: Placing a label based on a point's location within a polygon

texts:
I have a polygon dataset and a point data set with occupants. I need to label the occupants of the house within the polygon and need the label to show up on the side associated with its polygon.

Simple breakdown - if the house is on the right extremity of the plot, the label will need to be on the left so it visually looks like it belongs to that plot.  If the house is on the left extremity, I need the label to show up on the right of the point.

How can I make this dynamic? I can set the zones in maplex but that won't take into account the points placement within the polygon. There are a lot of points to manage so i don't want to convert anything/place them manually ideally.

edit: Using ArcGIS 10.2.1


texts: How to switch off symbol when label is unplaced due to conflicts?

texts:
Using either the standard ArcMap labelling engine, or the Maplex engine, it is possible to automatically omit labels from the map when the area is too congested.

Eg in the centre of this image, there are too many towns close together so their labels aren't placed:

Is there a similar method to switch off those towns' symbols as well?

Ideally I'm looking for something automated, which works based on the current viewport (in the same way that the labels are automatically re-positioned if you pan or zoom the map)


texts: Is a SRID an attribute of geometry or geometry column?

texts:
I'm not an expert. Yesterday I found out that SRID in PostGIS is property of the column - an actual constraint that is even stored in pg_constraints table and then retrieved through geometry_columns view. Previously I thought that SRID is set and stored per geometry record.
So given that, I now have several questions:

If it's an actual constraint why it's not enforced - e.g. why is that I can still write into the column a geometry with any SRID?
Why methods like ST_SRID or ST_SETSRID accept geometry as an argument rather than column name?
Also currently to fetch the geometries from DB we use local hardcoded map of SRIDs by region, can't we use SRIDs from geometry_columns instead?
What's the point of storing a SRID per column like that if it's not even used for anything anywhere?


texts: Adding temporal attributes of larger polygons onto many smaller overlaying polygons

texts:
I am currently working with rainfall data on a large grid layer and want to transfer the data onto smaller grids. In the image below the large blue polygons currently have the data stored in them and I want to smaller pink polygons to have the same data dependent on which blue polygon they lie within (which central point of blue polygon they are closest to).

The data in the large blue grid is in the following columns structure:

Location (corresponds to each polygon of the grid e.g. A1, A2, B1,
B2)
Date (the measures occur over a time period split up into equal
chunks in the format of text e.g. 'Time 1' 'Time 2' 'Time 3')
Mean
rainfall (a measure of rainfall averaging the rain across the time
period I chose)

There are 9 time chunks so for each blue grid square there are nine corresponding rows in the attribute table, each recording the location, date and mean rainfall, so for example in grid square G5 the structure is:

and so on for each grid cell in the table.
The pink squares are where I actually want the rainfall data. I've been trying different joins but it only takes one of the time values, whereas I need all 9 as the mean rainfall is dependent on the date.
How do I get it so that every pink square that overlays blue G5 contains all nine rows of information about G5, and do the same for each of the other blue squares with their overlaying pink squares too? So the end result should be this within the attribute table for the pink squares (where pink location = label for unique pink grids, no relationship to blue location names):

Then this is repeated for every pink square, rather than what has been happening which is only the mean rainfall for Time 1 being copied over to the pink square.


texts: Filtering repeated values from another layer?

texts:
I'm a complete noob when it comes to programing, and a not so experienced user of QGIS, at least not in depth.

Here's my problem:
I have two layers, lets say A and B.
When I create a new feature in layer B, the attributes window shows up to fill with information. One of this fields is meant to have values exclusively from a specific attribute from layer A. Lets say "Code".

I've managed to configure that field in layer B as a drop list that shows only that attribute from layer A.

The problem is it shows ALL attributes from that column, even if they are repeated.
For example, if layer A has 100 features with code "1", the drop list in the attributes of layer B will shows the code "1" 100 times.

So, how can I limit the drop list in B so it shows only exclusive values, instead of all existing values, even if repeated?


texts: Why does multi_user_mode have to be False in edit session on non-versioned dataset using ArcPy?

texts:
I'm in the process of implementing Mintx's answer to my question
What would cause a geoprocessing service to say "Cannot Open 'FeatureClass' Failed to Execute"?

However, I had another question come up. I figure the right way to insert records into a dataset is to use an edit session so that doesn't hold an exclusive lock for the duration of the time that an insert cursor is opened. But it only needs the exclusive lock for the duration that edits are saved.

So, I'm looking at the Editor class in ArcPy http://desktop.arcgis.com/en/arcmap/10.3/analyze/arcpy-data-access/editor.htm

In one of the code samples here, it says that startEditing()'s 2nd parameter, which is multi_user_mode, should be set to False for unversioned data... but it doesn't explain why:

# Start an edit session. Must provide the workspace.
edit = arcpy.da.Editor(workspace)

# Edit session is started without an undo/redo stack for versioned data
#  (for second argument, use False for unversioned data)
edit.startEditing(False, True)

# Start an edit operation
edit.startOperation()

# Insert a row into the table.
with arcpy.da.InsertCursor(fc, ('SHAPE@', 'Name')) as icur:
    icur.insertRow([(7642471.100, 686465.725), 'New School'])

# Stop the edit operation.
edit.stopOperation()

# Stop the edit session and save the changes
edit.stopEditing(True)

Here's the documentation on multi_user_mode:

  When False, you have full control of editing a nonversioned, or
  versioned dataset. If your dataset is nonversioned and you use
  stopEditing(False), your edit will not be committed (otherwise, if set
  to True, your edits will be committed). (The default value is True)

I'm a little bit confused because it mentions the behavior of multi_user_mode being set to False -- that you have 'full control' of editing a data set. (My best guess here is that 'full control' refers to having an exclusive lock on the dataset... Is this true?)

I'm just trying to understand what's going on with the database underneath in terms of transactions, commits, rollbacks, and locks.

With that, let me lay out some explicit questions:

What does edit.startEditing(False, False) do on a versioned dataset, and how does it differ from using edit.startEditing(False, True)?
What happens in the DBMS for non-versioned data that requires the use of edit.startEditing(False, False)?


texts:
I'm getting consistent, weird results from using Minimum Bounding Geometry to make circle polygons. I'm not sure if a datum issue, but I'm leaning more towards something wrong with Minimum Bounding Geometry tool. Here's the situation:

Goal is to acquire diameter in meters from minimum bounding polygon circles.

Python script works as follows:

Import Lat/Lon values with MakeXYEvent Layer (setting GeoCoordSys to D_North_American_1983)
Copy Features
Project points (to North America Albers Equal Area Conic)
Create Min. Bound Polygons around groups of points (ranging from 2 to over 50 points in a group).

Results seem reasonable for most polygons, however there are a good portion that the resulting circles wrap the globe. In several cases the points are clearly grouped in a small area off the coast, and the polygon is covering an enormous area of land, not even overlapping points. This in combination with "inconsistent extent" error makes me think it's a datum/project issue.

Troubleshooting efforts so far include

Points used to create the erroneous min bound circle outputs do not appear to have unusual lat/lon values.
Running Min. Bound Polygon to create a convex hull on points that were consistently creating crazy circles. Convex Hull created seemingly reasonable results.
Using convex hull polygon as input for min bound circle, and created same enormous circle.

Have you seen this before? Is this a case of choosing the wrong projection/datum? An error in Arc? An error in Min Bounding Geometry tool?

Thanks for input!

Sharon


texts:
I have a 2017 database for a road network. It has RUTM Coordinates, and other attributes. I have a 2018 database for the same road network. Due to the nature of GPS, the RUTM coordinates in the new database are offset with variance. So the same road doesn't line up on the new database. I want to take important attributes from the old database, and put it on the new database for the corresponding road segments. So I want to combine these databases into one database with the 2018 coordinates, but with some 2017 attributes.

How do I do this?

They share a few attributes, but they do not consistently line up with each other across databases.


texts: How to render a multi-layered (raster + vector) map to a file (PDF, SVG or JPEG, PNG)?

texts:
When using OpenLayers I can compose a map with several layers which is displayed nicely by my browser, but I need to do the same server side (no browser composing the layers), and I'm waiting a image file as output (ie PDF, SVG, JPEG or PNG).

I need to do composition with at least OSM and Vector layer types.

What are my solutions ?


texts: Checking small distance calculation in UTM zone 31 ETRS89

texts:
I'm afraid I've a very basic question about interpreting UTM grid values:

Are the grid references in metres?

I have data from the Spanish catastral map labelled as UTM Zone 31 ETRS89, and want to calculate some point-to-point distances, by pythagoras, over small distances used in urban planning.

If so, then over tens of metres we should expect extremely small errors from treating the ground as flat and simply using pythagoras, in order of 10-10 metre?  (Obviously other errors will dominate!)

Reasoning:

2 x π x 40 metres / 40,000,000 metre circumference = 6 x 10-6 radian
6 x 10-6 - sin(6 x 10-6) = 4 x 10-17  (very possibly beyond accuracy of calculator)
4 x 10-17 x 6,300,000 metre radius = 2 x 10-10

This is what I calculated for a building:

372954.477 4316151.012
372961.247 4316155.121 dx   6.770 dy   4.110 =>  7.920 m
372971.827 4316161.551 dx  10.580 dy   6.430 => 12.380 m
372980.437 4316147.931 dx   8.610 dy -13.620 => 16.113 m
372963.327 4316137.601 dx -17.110 dy -10.329 => 19.986 m
372954.477 4316151.012 dx  -8.850 dy  13.410 => 16.067 m


texts:
I have a set of locations each representing a service capacity. I also have a polygonal layer with each polygon representing local demand for that service. For each location, I would like to define its service catchment by summing up the demand values from its nearest polygons until they meet the service capacity of the location. I thought it might be easier to rasterize the demand layer and then do some cost distance assessment but I can't figure out how to do this by summing the attribute value to meet the local service value.

Image 1 shows the data I have, The location example has a service capacity of 1100 and the polygons represent local demand. Image 2 shows how I have manually selected polygons summing to close the capacity, this would represent the service catchment.Image 3 shows a rasterized version of demand

.

Anyone have an idea how this could be achieved?


texts: ArcGIS Server Object Extension for Analyzing Linearly Referenced Data

texts:
I have just begun learning about the ArcGIS Server Object Extension (SOE) capabilities, specificially with ArcGIS 10.

Is there an example available of an SOE that can return information about linearly referenced data?  For example, if I am using an Event Table to manage data about speed limits along a highway, I am trying to find an SOE that can return the exact speed limit, given a measurement along the highway.

In addition, I am trying to learn more about Custom SOEs being accessed through the ArcGIS Server REST service handler.  Does anyone know of any examples of something similar?

Thanks,
Seth


texts: RTK stream without base station in DJI Mavic 2 Enterprise Advanced

texts: New drone operator here. We recently acquired a DJI Mavic 2 Enterprise Advanced. It comes with an RTK Module. We are based in Iowa, USA and the state has a free Real-Time Network Service (NTRIP) available for all. On the DJI Pilot apps, the RTK menu, I am providing the following settings as shown in the image below. It connects to the service every 5/10 seconds and stays connected for 2-3 seconds then disconnected for another few seconds. DJI Pilot also notifies that the RTK connection is weak and the aircraft is unable to take off. Once I disable the RTK module, the GPS works fine and the flight works as expected. Is there any way of connecting the RTK module without using an expensive base station (Trimble or Leica)?


texts: Extracting Earthquake Depth from the USGS GeoJson Earthquake Feed for use with Openlayers

texts:
I have some GeoJson from the USGS as follows:

{"type":"Feature","properties":{"mag":4.3,"place":"30km ESE of Jarm, Afghanistan","time":1382069641720,"updated":1382071013039,"tz":270,"url":"http://earthquake.usgs.gov/earthquakes/eventpage/usb000kg6q","detail":"http://earthquake.usgs.gov/earthquakes/feed/v1.0/detail/usb000kg6q.geojson","felt":0,"cdi":1,"mmi":null,"alert":null,"status":"reviewed","tsunami":null,"sig":284,"net":"us","code":"b000kg6q","ids":",usb000kg6q,","sources":",us,","types":",cap,dyfi,general-link,geoserve,nearby-cities,origin,phase-data,tectonic-summary,","nst":null,"dmin":2.372,"rms":0.49,"gap":112,"magType":"mb","type":"earthquake","title":"M 4.3 - 30km ESE of Jarm, Afghanistan"},"geometry":{"type":"Point","coordinates":[71.1215,36.7111,215.63]},"id":"usb000kg6q"},

The geometry contains 3 dimensional data, where it is necessary to set the GeoJSON.ignoreExtraDims parameter to true to ignore that third dimension to load the Geojson into a Vector Layer

This third dimension appears to be the depth of the Earthquake! How can i get access to this if it does not appear in the data in the Vector Layer (It does not, I have checked, it is just ignored)


texts: Is it possible to access the QGIS processing-algorithm interfaces (GUI) with python?

texts:
I want to run some python code to access an algorithm in the processing toolbox. The result should be, that the GUI of the Algorithm pops up. (Similar to clicking on an algorithm in the Toolbox itself.)

processing.runalg('algorithm & parameters')

With this code I can run an algorithm within a script, but this is not what I am looking for. In QGIS 2.18 fTools are gone and replaced by processing-algorithms, but I doubt, that this was done using python.
So it seems possible, but is it possible with python?


texts: Landsat 8 surface reflectance data range and cloud mask uncertainty (Earth Engine)

texts:
I downloaded a composite using code given below, but all values are not looking like surface reflectance values (0..1), but range from 200 to 700, for example (like raw data digital numbers). Or am I wrong with such justification?

// Define AOI
var region = ee.Geometry.Polygon(
  [[[29.78, 51.42],
    [29.78, 51.13],
    [30.61, 51.13],
    [30.61, 51.42]]], null, false);

/**
 * Function to mask clouds based on the pixel_qa band of Landsat 8 SR data.
 * @param {ee.Image} image input Landsat 8 SR image
 * @return {ee.Image} cloudmasked Landsat 8 image
 */
function maskL8sr(image) {
  // Bits 3 and 5 are cloud shadow and cloud, respectively.
  var cloudShadowBitMask = (1 << 3);
  var cloudsBitMask = (1 << 5);
  // Get the pixel QA band.
  var qa = image.select('pixel_qa');
  // Both flags should be set to zero, indicating clear conditions.
  var mask = qa.bitwiseAnd(cloudShadowBitMask).eq(0)
    .and(qa.bitwiseAnd(cloudsBitMask).eq(0));
  return image.updateMask(mask);
}

var collection_2017 = ee.ImageCollection('LANDSAT/LC08/C01/T1_SR')
  .filterBounds(region)
  .filterDate('2017-05-20', '2017-09-20')
  .map(maskL8sr);

Export.image.toDrive({
  image: collection_2017.mean().clip(region),
  description: 'Landsat_Chernobyl_2017',
  region:region,
  scale: 30,
  crs: 'EPSG:32636'});

And how to specify cloud masking threshold? I have a function in this code but I am not sure how it masks clouds.


texts: How can one acquire information about direction of a one way road from OpenStreetMap data converted to a postresql database with osm2pgrouting?


texts: Storing date in m-dimension of PostGIS geometries

texts: Do you know if it is possible to assign a date (whatever the format) as the 4th dimension to a geometry in PostGIS? If so, does it recognize it as a date?


texts:
I want to modify the size of a raster considering reference points in PyQGIS 2.6. For this, I have the coordinates of four points that I want to be the new coordinates of the corners.
I have the following:
from processing.algs.gdal.GdalUtils import GdalUtils
src = "C:/raster_to_modify.grd"
points = "C:/file_with_points.points"
trans = "C:/raster_createdtrans.grd"
final = "C:/raster created.grd"

gcp = open(points, "rb")
hdr = gcp.readline()
command = ["gdal_translate"]
for line in gcp:
    x,y,col,row,e = line.split(",")
    command.append("-gcp")
    command.append("%s" % col)
    command.append("%s" % abs(float(row)))
    command.append("%s" % x)
    command.append("%s" % y)
    command.append(src)
    command.append(trans)
    GdalUtils.runGdal(command,None)

command = ["gdalwarp"]
command.extend(["-r","near","-order","3","-co","COMPRESS=NONE","-dstalpha"])
command.append(trans)
command.append(final)
GdalUtils.runGdal(command,None)

The points file has the structure: mapX,mapY,pixelX,pixelY,enable
When performing the process generates the file but not readjusted. I really appreciate your help to understand why it doesn't work or know if this is possible in Python without having to open it in QGIS.


texts: Setting SSL Cipher Suites in Portal Admin

texts:
I am trying to update the SSL cipher suites (to be in compliance with my org security requirements) at '/portal/portaladmin/security/sslCertificates/update'
according to this page

I am getting:  Error: One or more invalid HTTPS cipher suites

I have checked and all cipher suites I am using are compatible according to the linked page

I could not find any information on this issue. Has anyone successfully changed the cipher suites this way?

EDIT: The cipher suites I want to set:

TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384, TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, TLS_RSA_WITH_AES_256_GCM_SHA384, TLS_RSA_WITH_AES_128_GCM_SHA256, TLS_RSA_WITH_AES_256_CBC_SHA256, TLS_RSA_WITH_AES_128_CBC_SHA256, TLS_RSA_WITH_AES_256_CBC_SHA, TLS_RSA_WITH_AES_128_CBC_SHA


texts: Feature IDs table to Turn Feature Class in ArcGIS

texts:
I have a table of around 7,000 records that represents the restricted turns (illegal turns) in a city, and it looks like this:

The IDs in the table correspond to the Feature IDs in my streets layer involved in the restriction (for example, the first row represent an illegal turn involving 5 line features in that particular order).

Since, I'm using network analysis in ArcGIS 10.2.2 (Advanced License) to solve a Vehicle Routing problem, is there any quick way to build a Turn Feature Class including these 7,000 records without having to draw each one of them?


texts: Custom point markers in Matlab Mapping Toolbox?

texts:
I'm trying to find out if it's possible to create custom point markers (from some image files) in Matlab with Mapping Toolbox.

So far, I haven't found anything about this in their documentation. Online searches only yielded:

  No. The marker shapes are hard-coded and you cannot add new ones. If you want a custom
  marker, then at each point you want the marker, you will have to use line() or
  equivalent to draw the marker or image() or equivalent to draw in an image.

(Source: http://groups.google.com/group/comp.soft-sys.matlab/browse_thread/thread/4fe4e31f191f7080)


texts: ArcMap crashes after using "geocode addresses" tool

texts:
I'm working with ArcGIS 10.2 in a project where I need to publish my own geoprocessing service in order to Geocode a table of addresses. I tried creating models in model builder then publishing them and everything was working fine. But after trying to publish a model wher the input is an Excel file that I convert to a tableau and then geocode it, ArcMap crashed and since then everytime I try to run a model containing "Geocode addresses tool" ArcMap crashes. I tried to run a simple "Geocode addresses" from the toolbox and the toolbox crashes.

I tried deleting temp files and changing the "normal.mxt" and rebooting and the problem persists. I find this behavior strange since the same models were working before even in ArcGIS Server and now everytime a model is using "Geocode addresses" ArcMap crashes in the "geocoding addresses" step.


texts: How to apply a color gradient to a shapefile from QGIS console?

texts: Anyone knows how to do a color gradient from the console to a shapefile in QGIS (or in Python)? Like the image below.


texts: I tried to extrude walls in FME from chopped lines (2 vertices). I am using ground height to extrude.  The middle portion of the lines for the building slope roof is not extruding correctly.


texts: Bad corner coordinates transforming SRTM *.hgt files to GRD format using gdal_translate

texts:
I'm transforming some SRTM *hgt files (1 second resolution version) to GRD format using dal_translate. For example, one of my orders is:

gdal_translate -of AAIGrid N43W001.hgt N43W001.grd

The center of pixel coordinates for the lower left position in this file are lat=43º, lon=-1º, but the transformed GRD file has lower left coordinates lat=42.999861111111º, lon=-1.000138888889º, i.e., the coordinates correspond to the lower left corner of the lower left pixel, intead of its center.

I can't find any option in gdal_translate in order to deal with this problem. Am I using gdal_translate in an incorrect way?


texts: Passing attributes to neighbouring polygons

texts:
I have an ecosystem polygon layer that has been updated using a more recent tree cover layer (to remove cleared areas and also to re-align veg boundaries where growth has occured).

Where the polygons have been 'grown out', not all values have been passed along to the new, neighbouring polygon (only the actual RE value itself).  In other words, the existing polygon is in the data, with an adjoining polygon to represent the new area, which should be treated as the same RE unit).

What would be the best approach to re-attribute these polygons?


texts: Assigning value of list to field using ArcPy?

texts: I have used the addfield_management function to add a new field, and I want to assign the value of a existing list like [1,2,3,...]to the new field, any idea how to do it?


texts: Generate Mobile Map Cache from ArcObjects

texts:
As of ArcGIS 10, is there a way to generate a mobile map cache using ArcObjects?

This can be done in a stand-alone Python script:
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//003z00000005000000.htm

Thanks,
Seth


texts:
I am trying to download SoilGrids data with R following this tutorial. I have tried it on Windows and macOS with GDAL version 2.4.4 and 3.1.2, respectively, but none of them worked. It threw me errors like "ERROR 4: ...tileSG-007-062/tileSG-007-062_1-3.tif'not recognized as a supported file format", "ERROR 4 .../cec/cec_0-5cm_mean.vrt' not recognized as a supported file format" or sometimes ERROR 1.
It happened even when I used exactly the same codes shown in the tutorial. Would anyone help me with it?


texts: Toggle between custom basemaps (different projections/tile structures)

texts:
Wondering if it is possible to toggle between two basemaps with that have a different wkid and tile structure?

I have tried with a basemap gallery and a basemap toggle with no luck. We have one custom basemap and are trying to use the world imagery for the second. Is this possible? If not is there a way around it, by using something like a ArcGISImageServiceLayer?

Here are the examples I have been going off of:
https://geonet.esri.com/message/438609#438609


texts: Read status and XY-coordinates from GPS-widget with Python (QGIS 3)

texts:
Is there a way to access the status and the XY-coordinates from a GPS-connection established by the GPS-widget in QGIS 3 via python?
I want to establish the connection with the widget to have better control of the connection (like changing ports) and status checks, but need the coordinates inside a python plugin.


texts: No module named 'osgeo' after installing GDAL on Mac

texts:
I installed GDAL on Mac and it was successful because when I type in the terminal : gdalinfo --version it renders me the right version. The issue is when I switch to Pycharm or the default IDLE of Python and I run this simple program:

import sys
from osgeo import gdal

version_num = int(gdal.VersionInfo('VERSION_NUM'))
if version_num < 1100000:
    sys.exit('ERROR: Python bindings of GDAL 1.10 or later required')

It returns me this error :

Traceback (most recent call last):
  File "/Users/sigc2sige/Desktop/Zak/Gdal/app1.py", line 2, in <module>
    from osgeo import gdal
ModuleNotFoundError: No module named 'osgeo'

Process finished with exit code 1

Any ideas please to solve this issue?


texts: Getting syntax error in Label Expression

texts:
I am receiving the SyntaxError: invalid syntax(string, line 26)(last line in this case) when I am trying to make this label expression for use in ArcMap. As far as I can see, everything looks right. I believe the indentations are correct and I've tried them in a few different places to make sure. Any ideas?

def FindLabel ( [SWSID] ):
  import arcpy
  myDataTable = "Muskoka_100miRadial_Combined" #insert data table name
  myComponent = "Muskoka Airport" #insert component name
  myScreeningLevel = "50" #insert exceedance  level
  myQuerySelect = '"SWS_ID"' + " = '" + [SWSID] + "' and " + '"component"' + " like '" + myComponent + "%'"
  myFieldsQuerySelect = "OBJECTID; Tavg_First; Tavg_Last_; Tavg_Perce; SF_First_D; SF_Last_da; SF_Percent; SD_First_D; SD_Last_da; SD_Percent; Rain_First; Rain_Last_; Rain_Perce"
  mySortQuerySelect = "SWSID"
  myText = ""
  mxd = mxd = arcpy.mapping.MapDocument("CURRENT")
    for table in arcpy.mapping.ListTableViews(mxd):
     if table.name == myDataTable:
       rows = arcpy.SearchCursor(table, myQuerySelect, "", myFieldsQuerySelect, mySortQuerySelect)
       myText = "<BOL>" + [SWSID] + "</BOL>\n" + "<ITA>" + myComponent + "</ITA>" + "\n"
       currentState = ""
       for row in rows:
         if currentState != row.OBJECTID:
            currentState = row.OBJECTID
         if float(row.SF_Percent_Comp) <= float(myScreeningLevel):
           myText = myText + str(int(row.Tavg_First)) + ' ' + str(int(row.Tavg_Last_)) + ' ' + str(int(row.Tavg_Perce)) + "</CLR></BOL> " + "\n" + str(int(row.SF_First_D)) + ' ' + str(int(row.SF_Last_da)) + ' ' + str(int(row.SF_Percent)) + "<BOL><CLR red = '255'>" + "\n"+ str(int(row.SD_First_D)) + ' ' + str(int(row.SD_Last_da)) + ' ' + str(int(row.SD_Percent)) + "</CLR></BOL> " + "\n" + str(int(row.Rain_First)) + ' ' + str(int(row.Rain_Last_)) + ' ' + str(int(row.Rain_Perce)) + "</CLR></BOL> " + "\n"
         else:
           myText = myText + str(int(row.Tavg_First)) + ' ' + str(int(row.Tavg_Last_)) + ' ' + str(int(row.Tavg_Perce)) + "</CLR></BOL> " + "\n" + str(int(row.SF_First_D)) + ' ' + str(int(row.SF_Last_da)) + ' ' + str(int(row.SF_Percent)) + "</CLR><BOL>" + "\n"+ str(int(row.SD_First_D)) + ' ' + str(int(row.SD_Last_da)) + ' ' + str(int(row.SD_Percent)) + "</CLR></BOL> " + "\n" + str(int(row.Rain_First)) + ' ' + str(int(row.Rain_Last_)) + ' ' + str(int(row.Rain_Perce)) + "</CLR></BOL> " + "\n"
       return myText:


texts:
I want to use GDAL/OGR to extract pixel values from a raster file. The extraction should be based on polygons, stored in a shapefile. My thought was to iterate over the features in the shapefile, extract the pixel values of those pixels that have there center point within the polygon and calculate a percentile from those values. When this is done I want to write the calculated percentile back to the polygon and go on with the next polygon.

Iterating over the polygons is easy, but what I do not get is how to extract the pixel values from the pixels, covered by the polygon.

I'm using Python.

Could somebody help me at this point?


texts: Converting multicolumns CSV to Raster Format

texts:
I need to convert multicolumn CSV file in a raster.
I read some similar question, but my problem is that I have different columns in addition to "longitude" and "latitude" (I would like to manage a 20 years data). I don't want and cannot separate the columns into other files, are too many. Values are average temperature per year. Header Columns are:
lat, lon, year(1), year(2), year(3)... year(n).
Should I first somehow order my CSV and the translate it in a multiband raster?


texts: How can I summarize the values of a raster to make a clear legend?

texts: I produced a relief map out of a ASTER Satellite Picture by using a colour ramp (Symbology -> band rendering). I want to make a map out of that in the Print Composer but the Legend is very confusing with all that values. I'd like to have a legend which shows values like 0-100 m = darkgreen, 101-200 m = green, ..., 1200-1300 = dark red.


texts: Performing Feature to Point (no advanced license) using ArcPy?

texts: I have a set of polygons I have calculated the centroids of, but am having trouble finding a way to output these values to a point shapefile. I dabbled with arcpy.MakeXYEvents_management, but it only creates a temporary layer file.


texts:
I would like to update one ore more fields of my attribute table on demand (f.e. using a QGIS Action) with one simple click.
For now I have to open attribute table or the layer properties, start field calculator, choose the field I want to update, type or paste my expression and run it for every field I need to update.
I tried to use the model builder but I found no way, to simply update a field within the layer without creating a new layer.
Virtual Fields are not helping me in this way, because the recalculation will be time consuming (complex aggregate expression).


texts: QGIS include action (hyperlink) in composer output

texts: Is there a way to include the action "open url" in my map created in composer? I'm open to the final export being either a pdf or an image, but I'd like the end user to be able to click on different items within the map and it open the specified url (I've already set this up in the action menu in QGIS).


texts: How to limit vertically the extent of an OpenLayers map?

texts:
When I pan north, the map goes out and I see the white background of my HTML. I want to pan vertically and the map to block when it reaches the top (or bottom, respectively).

I have tried to put bounds, but this solution puts also bounds horizontally. I want to be able to pan infinitely left or right, but limit the panning up and down.

How could I do this?


texts: Assigning one-to-many polygon to .csv data in ArcGIS for Desktop?

texts:
So I am currently working with two separate files. One is a polygon feature class detailing a specific countries' subdistricts. These subdistricts are identified using a specific alpha-numeric code. The other file is a .csv file containing information on humanitarian programs currently in place within this country. Each program is identified by its location, down to the subdistrict (using the same code). There are numerous subdistricts with multiple programs.

My end goal is to assign each individual program the polygon of the subdistrict where it is located. To this end, I have created a relationship class between the two (one-to-many). However, it seems this will not help me accomplish my goal.

Is there any way I can accomplish this? One idea would be to export the polygon spatial data to .csv format, allowing a join, but I'm not sure if that is possible.


texts: How to calculate distances between addresses and cities and coast line?

texts:
I am totally new to GIS, and so I apologize if my question is not clear enough. My basic problem is the following:

I have about 160,000 Danish addresses with longitude and latitude for each address.
I would like to calculate the distance to the nearest big city (preferably by road and not straight line), and the distance to the coast.
I have access to a topographical map of the roads and cities in Denmark in the scale of 1:1000000.
The data structure is vector.
The format is GDB (ArcGIS).
The coordinate system is UTM32-ETRS89.
I use windows 7 64 bit.

I have the following question:

Is there a free GIS to work with the GDB format (and preferably a reference to a tutorial or similar for absolute beginners)?

Any comments are welcome, and I gladly provide more info if needed.

Thanks a lot!!


texts:
Is there any way to merge several processes in QGIS3 into one process?

Or is there a way to look at the source code of different processes under QGIS3 and combine them under one function?

I am trying to create one file (in Python) with all the processes under one single process.


texts: Slope tool error when running from arcObject add-in tool

texts:
My problem is related with Global DEM to Slope calculation. The slope tool works when raster is projected or the map is projected where the raster is added. And also, if the raster and map both are not projected, slope tool runs well but may be the result is not perfect.

Problem is when I run the slope tool from my c# code and pass the raster layer to slope tool.
Only when the raster is projected, the tool runs well otherwise reports a crash. In fact when the map is projected, tool reports a crash.

There I could not find a way that I pass the map projection system to the tool. At the same time, when I pass a Z-factor value, why does it matter if the raster data is projected or not?


texts: How to scrape addresses from a web page for geocoding purposes?

texts: I am trying to get addresses from a web page for mapping purposes. I know I could copy and paste the addresses into an Excel file and geocode them but I was wondering if there was any faster way to get the address from a web page and create a point location file?


texts:
My university desires to switch from using ArcGIS to using QGIS and therefore I have to figure out whether the exercises that are used in lectures can be performed using QGIS.

I have an .AUX file that can be used in ArcGIS. When I want to open this file in QGIS, the file shows up in the layers list but no image is drawn on the canvas. Also, there is no attribute table. In ArcGIS, there is an image drawn and there is an attribute table. What could cause these differences and how to overcome this problem?

Thanks


texts: how to make the translation between latitude/longitude and screen pixels

texts:
The earth is three dimension object while our screen is two-dimension.

So when we use the gis software to display the geographic data, how do they handle the translation between  latitude/longitude and screen pixels?

I know the projection which will translate the latitude/longitude to a two-dimension point. But what is the unit of the two-dimension point? Is it the 'pixel`?

Update:

To make this question clearer:

The rectangle is the screen view port(with size 800x600), and I know the center coordinate(65E,26N), then how to get the coordinate of the four corner?


texts:
When serving RPF imagery (Raster Product Format) from a WMS, will the WMS handle which layer should be on top? For example, let's say I request layer X and layer Y in some bounding box, and layer X should be displayed at scale 1:10000 and layer Y should be displayed at scale 1:20000

I would expect that at scale 1:5000, layer X would show up since it is the higher resolution image (since it displays at the lower scale). Then I would expect at scale 1:15000, layer Y would show up. Is this typical WMS server behavior?


texts: how to reproject the coordinate system from WGS84 to UTM with ProjNET

texts:
I'm new to ProjNET and NetTopologySuite, I get some points with Lon/Lat in WGS84, and the distance between two points is not with the unit of meter, so I want to reproject the coordinate system from WGS84 to UTM, here is the code

        NetTopologySuite.Geometries.PrecisionModel precisionModel = new NetTopologySuite.Geometries.PrecisionModel(GeoAPI.Geometries.PrecisionModels.Floating);

        ProjNet.CoordinateSystems.CoordinateSystem wgs84 = ProjNet.CoordinateSystems.GeographicCoordinateSystem.WGS84;
        ProjNet.CoordinateSystems.CoordinateSystem utm50 = ProjNet.CoordinateSystems.ProjectedCoordinateSystem.WGS84_UTM(50, true);

        int SRID_wgs84 = Convert.ToInt32(wgs84.AuthorityCode);    //WGS84 SRID
        int SRID_utm50 = Convert.ToInt32(utm50.AuthorityCode);    //UTM50 SRID

        ProjNet.CoordinateSystems.Transformations.CoordinateTransformationFactory ctFact = new ProjNet.CoordinateSystems.Transformations.CoordinateTransformationFactory();
        GeoAPI.CoordinateSystems.Transformations.ICoordinateTransformation transformation = ctFact.CreateFromCoordinateSystems(wgs84, utm50);

        NetTopologySuite.Geometries.GeometryFactory factory_wgs84 = new NetTopologySuite.Geometries.GeometryFactory(precisionModel, SRID_wgs84);

        var q1_rad_wgs84 = factory_wgs84.CreatePoint(new GeoAPI.Geometries.Coordinate(Deg2Rad(117.977319), Deg2Rad(30.957558)));
        var q2_rad_wgs84 = factory_wgs84.CreatePoint(new GeoAPI.Geometries.Coordinate(Deg2Rad(117.577319), Deg2Rad(30.757558)));

        double[] coords_p1 = transformation.MathTransform.Transform(new double[] { q1_rad_wgs84.X, q1_rad_wgs84.Y });
        double[] coords_p2 = transformation.MathTransform.Transform(new double[] { q2_rad_wgs84.X, q2_rad_wgs84.Y });

        NetTopologySuite.Geometries.GeometryFactory factory_utm50 = new NetTopologySuite.Geometries.GeometryFactory(precisionModel, SRID_utm50);

        var p1_utm50 = factory_utm50.CreatePoint(new GeoAPI.Geometries.Coordinate(coords_p1[0], coords_p1[1]));
        var p2_utm50 = factory_utm50.CreatePoint(new GeoAPI.Geometries.Coordinate(coords_p2[0], coords_p2[1]));

        var distance_in_meter = p1_utm50.Distance(p2_utm50);

but I found that, after reproject the coordinate, the value of distance_in_meter is wrong.

Is there any problems with my codes?


texts: I have sample data that was collected in lines.  I would like to rotate the data to North-South so that I can rasterize it, then back to the original NAD83 Zone Projection where it's situated at an angle from North.


texts: How do I find license number for ArcGIS Desktop?

texts:
I have a machine with ArcGIS for Desktop 10.0 installed on it.

I need to find out which license it's using.

The machine is single use ArcEditor and was authorized online.

How can I find what the license number is?


texts: Where is qgis getting the NO DATA value from?

texts:
I have a project that contains an 8-bit paletted layer (call it the mask layer)  and a float 32 single band layer (call this the clip layer). I create a new raster by using the raster calculator, defining the extent to match the clip layer, and the value is defined as

(mask@1 >= 0) * clip@1

The resulting raster, when viewed with gdalinfo, has a NoData value of -3.4028234... e+038. Yet the input clip layer has no NoData value. Where is QGIS getting this NoData value from?


texts:
I am having trouble merging different layers in ArcScene. As there is no such thing as the "Georeferencing" used in ArcMap, I am not able to view two different Layers in one document.

Is there anyway to overlay two layers and show them in the same document? Or maybe any tool to spatial reference layers in a different kind of raster?


texts: Flipping multiple lines in Arcmap 10.4 (Basic Package)

texts:
I am working on a detailed stream edit and noticed that there are a lot of streams that need to be flipped due to the flow being incorrect based on direction. I was wondering if there was a script that someone had where I could achieve this task?
And if so, can you describe to me how it works? My Python is a little rusty.

I am running ArcMap Basic so I don't have any extensions that I'm used to, otherwise this wouldn't be much of an issue.


texts: edits to attribute table in qgis do not show up in arcgis

texts: I have received a point file that was made in QGIS.  if a row is deleted in QGIS it appears to be deleted, in QGIS.  If I import that shp file into arcgis the attribute still shows the rows that were deleted in QGIS.  If I then export the shp file in arcgis and import it to QGIS, all the rows show - it is as if nothing was deleted.  Has anyone else experienced this?  I am using ver2.10.1-Pisa


texts:
I have previously asked question here but it was closed because I did not react fast enough I think. NEvertheless, my problem is still the same: I have a set of points (meteorological stations) with 5km buffers around them. Additionally, I have a set of polygons (municipalities) in which those stations are located. Each station buffer can be over 1,2,3... polygons and those can be completly different polygons.

I would like to have data on how much of the buffer is filled by each polygon but I was not able to find a function or a way to do it. So for example for point A I would have that in the buffer of 5km there is 80% of polygon B and 20% of polygon C as the output, so 4 values, two for IDs of the polygons and 2 for the percentage overlap (it could be only 2 values for other buffer or 6 etc. etc.).

Main difference to the other similar question provided is that I have 2 vector layers (Buffer with 500 buffers and Municipalities a shape file with 500 different polygons). Previous questions were analyzing this question in situations in which I know precisely the polygons and buffers analyzed, at least that is how I understood them, so after trying to use those approaches on my dataset I was not able to replicate them.


texts: I work for an train enterprise and we want to develop a SIG. The main goal is better property management. The main data to manage are dwg plans. My job is to write a process to introduce this plan in a SIG (QGIS). How can I do this?


texts: Why are Differential Correction services unable to transfer files for a 24-hour period?

texts:
Over the past year I have gone out and gathered Feature points using a Trimble GPS Device.

When I'm done, I'll come back to the office and try to perform Differential Correction using  Pathfinder Office (v5.60).

It seems that quite often I am "Unable to transfer" the files in order to post process and correct my GPS data.

Most research I've done on this topic indicates: "Wait for 24 hours and then try again."

Do I just have bad timing, or are these services regularly not available [whether for updates or servicing]?

The first two are CORS and the third is USDA.


texts: Intersection of two tables using the matching values in multiple fields

texts:
Primary usage of ArcGIS Desktop Basic:
I have to find the intersection of two tables in the same file geodatabase based on the values in multiple fields. Almost all queries to find some help are multiple field queries in one joined table or spatial in nature. The first is just wrong.
For the second, I can't assume a spatial accuracy in Table B (below), some elements have already shown to be out side of their geographic range. And that's ultimately the end goal of the project: to improve the spatial accuracy of Table B using Table A.

I have to find the records in A that match records in B, but not all records in B are in A.

Tables:
A (0.5M records)
B (0.4M records)

Fields to return:
A.1, A.10, A.11
B.1

Fields to match.
I have assured myself that the fields are of the same type (Text/String, Integer, etc) and that the pairings below are type and value matched. Some of the records in A are going to match some of the records in B.

A.2=B.2
A.3=B.3
A.4=B.4
A.5=B.5
A.6=B.6

Using the ESRI "Make Query Table" in 10.2 basic, I used this as the query:

`A.2=B.2 and A.3=B.3 and A.4=B.4 and A.5=B.5 and A.6=B.6`

Didn't specify any keys.

This returns with the message that there is an error with the expression and invalid SQL statement used.

Making the table on just field 6 takes less than a second but the table fails to open. Field 6 is the least granular.

I have expended my knowledge and feel I won't find the answer previously asked on the internet. This is probably just a database question and not a spatial issue, but I am using spatial data.

UPDATE:
I worked on it today (Sunday) some more. Created a new text field (let's call it 20) and populated by concatenating all the fields together successfully so that
    'A.20 = A.2 & A.3 & A.4 & A.5 & A.6'
    'B.20 = B.2 & B.3 & B.4 & B.5 & B.6'
This seemed to work perfectly using only one field to match, except it returned only 2/3 of the expected records. Field 5 has high granularity and removing it from consideration returned 160% of the expected records.
Does the "Make Query Table" tool have a limit to the number of fields it can access?


texts:
In recent years I have used this source https://dds.cr.usgs.gov/srtm/version2_1/SRTM3/ to retrieve elevation data from files in .hgt format.
The problem is that these data have holes, so I'm looking for a more recent source of SRTM data, which I found here http://srtm.csi.cgiar.org/srtmdata/ with .tiff format files

The holes have been filled, that's good, but the overall quality of the data returned is really worse, and I do not understand why.

I made an example of traces on contour lines using both sources, and here are the results I get: https://www.visugpx.com/yXT5LMErgk

You can compare the graphs for traces on 500-meter contour lines (on a steep terrain), 320 meters (hilly terrain) and 210 meters (flat terrain), and see that for the SRTM v2 .hgt source I have a margin an error of a few meters, while for the source SRTM VR .tiff there is up to 30 meters difference.

Is this problem known? Are there other sources you would recommend?


texts: Is it possible to create browser-specific CartoCSS?

texts:
I can't think of many practical uses for this, so it probably isn't implemented, but I have an edge-case desire for it so I thought I'd ask.

Basically I'm creating a Torque animation in CartoDB of natural disaster data from FEMA. So it shows all the disaster declarations by month and county they were declared in. It runs and looks great in Chrome and even IE.

Surprisingly, though, it freezes up a lot for me in Firefox -- in particular around September 2005 when Katrina hit and disasters were declared in basically every county east of the Mississippi. Lots of simultaneous points grind it to a halt for several seconds on my test computer.

Playing around with the settings, I came to the conclusion I can fix it by changing the composite operations (how CartoDB visually blends overlapping geometry). The setting I find the best looking, "lighter," is apparently more graphically intensive than one like "source-over." Side-by-side comparison below the post.

I want to keep "lighter" for most browsers, and have it gracefully degrade to "source-over" for Firefox. Is this possible, or do I just have to suck it up and use source-over?


texts: Geoserver WFS Feature Schema Enumeration of Strings

texts:
Basically, I'm trying to limit the values that can be provided by a WFS transaction. So the original schema I've got for this simple test feature here

<xsd:complexType name="secondfeatureType">
    <xsd:complexContent>
        <xsd:extension base="gml:AbstractFeatureType">
            <xsd:sequence>
                <xsd:element maxOccurs="1" minOccurs="1" name="objectid" nillable="false" type="xsd:int"/>
                <xsd:element maxOccurs="1" minOccurs="0" name="color" nillable="true" type="xsd:string"/>
                <xsd:element maxOccurs="1" minOccurs="0" name="shape" nillable="true" type="gml:GeometryPropertyType"/>
            </xsd:sequence>
        </xsd:extension>
    </xsd:complexContent>
</xsd:complexType>
<xsd:element name="secondfeature" substitutionGroup="gml:_Feature" type="geofeatures:secondfeatureType"/>

But I want to limit the value of color to several options: 'Red', 'Green', 'Blue'

I tried creating the following schema for Geoserver to use for this feature:

<xsd:simpleType name="colorType" final="restriction">
    <xsd:restriction base="xsd:string">
        <xsd:enumeration value="Red"/>
        <xsd:enumeration value="Green"/>
        <xsd:enumeration value="Blue"/>
    </xsd:restriction>
</xsd:simpleType>
<xsd:complexType name="secondfeatureType">
    <xsd:complexContent>
        <xsd:extension base="gml:AbstractFeatureType">
            <xsd:sequence>
                <xsd:element maxOccurs="1" minOccurs="1" name="objectid" nillable="false" type="xsd:int"/>
                <xsd:element maxOccurs="1" minOccurs="0" name="color" nillable="true" type="colorType"/>
                <xsd:element maxOccurs="1" minOccurs="0" name="shape" nillable="true" type="gml:GeometryPropertyType"/>
            </xsd:sequence>
        </xsd:extension>
    </xsd:complexContent>
</xsd:complexType>
<xsd:element name="secondfeature" substitutionGroup="gml:_Feature" type="geofeatures:secondfeatureType"/>

But the result is that any Insert Transaction I attempt to perform for this feature, the color value ends up being an empty string. It's the same result whether I try and create a feature with a color of "red" or deliberately bad value like "badvalue".

Is something like this even possible with GeoServer and WFS? If so, what do I need to change to make this work?


texts: raster data i have downloaded from CGIAR, Which contains .ovr files. It is not opening in Arcgis. How to open .ovr files and how to process them?


texts: Remove duplicates from an Image Collection in Google Earth Engine

texts:
I've been working with Sentinel-2 level 2A Image Collection in Google Earth Engine (GEE).
I noted that on some dates, for the same pixel, there are 2 or more images.
They were taken on the same day and the same hour (sometimes the difference is 1 second) though the reflectance values are different.
For instance, adding a point (pt) of coordinates 11.65, 37.34 and checking scenes of the 2021-10-02, it appears to be two images on the same day.
Reflectance values are different for all bands.
if you want to try, you just need to write the following code in GEE
var pt=ee.Geometry.Point(11.65, 37.34);
var start='2020-02-09';
var end='2020-02-11';
var sentinel_col=ee.ImageCollection("COPERNICUS/S2_SR")
                       .filterBounds(pt)
                       .filterDate(start,end);
print(sentinel_col)

Now my questions:

Why does this happen?
Is there a way to remove duplicates from the collection by means of GEE?
Of course over a time span it occurs multiple times for different dates. I want to remove all the duplicates or maybe merging the scenes with the same date and getting averaged values for the bands.


texts:
I am working with OpenLayers and GeoExt and I have the following problem:

I have a point vector layer and I want to create a style that contains 2 symbolizers.
In this example they show how this could be achieved with Geo Ext Feature Renderer. My question is: how do I connect the renderer to the layer once I create it?
I saw that GeoExt.FeatureRenderer has 'feature' as a config option, so I tried to apply it to one feature in my vector layer, but the feature is still displayed with the vector layer's default style.
This is a simple code of what I tried to do:

map = new OpenLayers.Map('map_element');
var ol = new OpenLayers.Layer.OSM();
map.addLayer(ol);
map.setCenter(new OpenLayers.LonLat(16.371,48.209).transform(new OpenLayers.Projection("EPSG:4326"), new OpenLayers.Projection("EPSG:900913")), 0 );

var vector_feature = new OpenLayers.Feature.Vector(new OpenLayers.Geometry.Point(0,0));
var vector_layer = new OpenLayers.Layer.Vector();
vector_layer.addFeatures([vector_feature]);
var multipleSymbol = [{
                            pointRadius: 8,
                            fillColor:"green",
                            strokeColor:"#000",
                            strokeWidth:1
                        },{
                            graphicName:"star",
                            pointRadius:5,
                            fillColor:"white"
                        }];
var config_options ={symbolType: 'Point',
            symbolizers:multipleSymbol,
            feature: vector_feature,
            xtype:'gx_renderer'};
Ext.Loader.load(['GeoExt.FeatureRenderer']);
Ext.onReady(function() { Ext.create(config_options)});
map.addLayer(vector_layer);

Thanks for your help!
Raluca