I'm trying to add a buffer to a CSV layer, in QGIS, which is overlaid onto an OpenStreetMap layer but I do not know how to change the units from degrees to meters. I've tried to change the CRS to EPSG 3857 which does change the units to meters but then the points are not where they are supposed to be on the OpenStreetMap overlay and seem to be at a completely different scale because I have to zoom into the ocean to see them. Even when I set the OpenStreetMap layer to EPSG 3857 it seems to be a completely different scale. Just wondering if if there is a way to change the buffer unit to meters but keep using EPSG 4326 as then all my layers seem to be at the right scale.
The problem   I have tens of thousands of small polygons for which I want to create buffer/doughnuts for, but I don’t get the units right. I want meters and not degrees, and changing to (what I think is) the right CRS my layer doesn’t longer show. The polygons are small farming plots. I work in QGIS 3.4.15.   Let me take you through it  I start by adding a vector layer. I opt for ‘Directory’ as a source type (Encoding: UTF-8 by default) and under Source (Type: UK. NTF2 by default) I point to the folder in which I store the shapefile.   The default CRS is set to EPSG:4326 – WGS 84, for both layer and the project (checked in bottom right), and unit is thus in degrees. I add the layer world map (EPSG:4326 – WGS 84 by default) by taping “world” in the coordinate box in the middle bottom, I also add Open street map (EPSG:3857 – WGS 84 / Pseudo-Mercator by default) from XYZ Tiles. The polygons appear nicely on the map considering some are just adjacent to the nearby lake, many nicely adjacent to roads, etc.   When attempting to do buffers the distance is obviously set to degrees. I have tried to change the CRS, both for the layer(s) and the projects, but without luck. After researching (e.g. here: ) I believe that the correct CSR would be Arc 1960 / UTM zone 36S EPSG:21036 (it is my understanding that either 36N or 36S would work as the polygons appear both south and north of, but close enough to the equator). When setting the mentioned CRS for my polygon layer, the polygons disappear from the map, and remain gone even after setting the project CSR (by bottom right) to the same. It seems that whenever I try with different CRS in UTM, the layer doesn’t show. Does this mean that the polygons are somehow not compatible with units in meter? Is there an issue with importing the .prj file?  Other things I've tried:   I have made a good attempt searching for solutions. I have ensured that the polygon layer is on top of the layers list. I have ensured the file names are identical and tried all different suitable CRS I can think of. I have seen similar questions been solved by saving the .shp 'as', but I don't think that's my issue as it's already a .shp file. Can it be the case that I need to perform a datum transformation? I gave it a shot using a transformation code (1122) provided by above link, but then the polygons were projected on the Antarctica on the world map, so obviously something went quite wrong...   Note that when I have changed to what I believe is the right CRS I can execute buffers in units of meters, however, they do not appear on the window…
Installing from source. How to resolve dependencies without destroying the package manager Detecting start bit in software UART I'm experimenting with writing a software UART on my microcontroller using GPIO pins. This is to temporarily add a UART channel on a project until we get the new design implemented that uses a uC with more UART ports.  What I'm having difficulty with is correctly detecting a start bit in a serial stream. The source of the stream is external and doesn't care when my device powers up. So it's very likely that my device will power on and start seeing data bits in the middle of a byte transmission. Undoubtedly, that will cause my software UART to read erroneous values, as it won't be able to tell the difference between a start bit and any other high-to-low transition.  Is this an inevitable issue with a UART channel? Or is there some clever trick that the uC manufacturers use in their hardware UARTs? How do I get the distance meter value between two geometries in PostGIS? I have a simple question about calculating distances in PostGIS.  I would like to get the distance between two geometries. I am using this sid : 4269 in meters what i am doing now is this : ST_Distance((a.geom,b.geom)) FROM ... but I am getting result in degrees. I think that I should work with geography but how can I cast a geom to a geography? I tried with (a.geom::geography) but i am getting an error.  What can I do to get my result in meters?   Thank You Ubuntu Won't Boot After Install on Samsung NP915S3G: error "All boot options are tried." So yesterday I went ahead and bought the Samsung NP915S3G (ATIV Book 9 Lite) and installed Tahr in hope that everything would go smoothly. For the most part it; everything necessary seems to work off the bat. Unfortunately when I restart it, nothing boots. I erased Windows so that's obviously not an option, but the computer seems pretty dead certain that there's nothing there to boot. I think this might have a lot to do with UEFI which is a field I have next to no experience with. There also seems to be a fat32 partition that consistently reappears when I delete it.   Any help is much appreciated, thanks. As a bulk sender, is there a way to make Gmail show my avatar?    I would like to obtain this without creating a Google Account.  Maybe embedding my vCard? Or maybe ? What if I offer a bounty and don't get any good answers? I have started a bounty:   It expires in 3 days. I don't have an appropriate answer to accept, and the only answer which it has gotten has no votes.  So am I going to simply lose 100 reputation without getting a satisfactory answer?  Or should I accept the lone inappropriate answer so that I will not lose my right to accept answers to any questions which I might ask in the future, which is what the bounty rules claim? Image of Stack Exchange button is blocked by Adblock Chrome and IE 11 are fine, I'm only able to reproduce this in Firefox. Using version 27.0.1 on Windows 7. Meta as well as all the other sites are affected.        I can still see the hover effect, but the image is gone. I see this in Firebug:        The image doesn't show up in the Network tab. I am able to see the image by visiting  which goes to   I've done Ctrl-F5, I've cleared the cache and I've tried Private Browsing. Possibly related to  ? Display SharePoint Online in an iframe on different domain We would like to display pages from SharePoint Online in an iframe of a Page hosted somewhere else, e.g. in an Azure Web App:  &lt;iframe src="https://site.sharepoint.com/"&gt;&lt;/iframe&gt;   When we do this (in Chrome for example), we get the following error:     Refused to display " ⏎                      Home.aspx" in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'.   A Page from SharePoint 2013 (on premise) can be displayed in an iframe from a Page hosted on another domain, if the following control is added to the head of the master page:  &lt;WebPartPages:AllowFraming runat="server" /&gt;   However if this control is not added to the master-page, then we also get the above mentioned error.  As far as I know there is no possibility to adjust the master-page in a SharePoint Online Team Site. Is that correct?   In a Publishing Site you are allowed to adjust the master-page, or even add a new one. But I can't find anything similar in Team Sites.  Does anybody know if it is somehow possible to configure domains which do not fall under the "X-FRAME-OPTIONS: SAMEORIGIN"-policy in a SharePoint Online environment? Or if there is another possibility to display SharePoint Online content in an iframe on a different domain. I checked google, checked the Site settings and checked the Office 365 admin center, but didn't find anything. Biliniear form to inner product Let $f:V\times V\rightarrow F$ be a bilinear form in a finite inner product space V.  If $F=R$, how can I prove that there exists a single linear transformation $T:V \rightarrow V$ so that for each $v,u\in V$, $f(u,v) = (Tu, v)$ ?  Would that sill be the case if $F=C$? Which is correct: "what if there was" or "what if there were"? Possible Duplicate:          Is this correct grammar?     What if there was a Stack Overflow on…    Shouldn't it be "what if there were a Stack Overflow on…"? Alternate moves, first one to roll a 6 wins: what's the probability of winning? Question: Players A and B play a sequence of independent games. Player A starts and throws a fair die and wins on a "six". If she fails then player B throws the same die and wins on a "six" or fails otherwise. If she fails then player A gets the die and throws again, and so on. The first player to throw a "six" wins. Find the probability that player A wins.  Here is what I have done:  A wins right away: $\dfrac{1}{6}$  A fails B wins: $\dfrac{5}{6}\times \dfrac{1}{6}$  A fails B fails A wins: $\dfrac{5}{6}\times \dfrac{5}{6}\times \dfrac{1}{6}$  Unlike another similar question which the player B can win on "five" and "six" after player A fails on the first throw, in this case, the games do not seem to have an endpoint. How should I calculate the probability that player A wins then? Can black holes actually merge? If time stops at the event horizon, can we ever detect two black holes merging? In other words, if you are a short distance away, would you encounter a spherically symmetric gravitational field, or a dipole field? Where does the phrase "Scare the Dickens out of..." originate from? Where does the phrase "Scare the Dickens out of..." originate from? And does it refer to Charles Dickens? How to map inherited entities in EF code-first Does the war have an ending in Planetside 2? As enemy bases are captured, they just seem to respawn right in the middle of friendly captured territory. This is looking like a perpetual cycle, and none of the three teams ever gets closer than to the very edge of winning the whole continent, only to lose lots of territory again.  So is this by design? Is Planetside 2 eternally to be at war, with no winner ever? I was hoping it would be more like a 'match'. I admit that both are almost the same thing, but there is at least the closure of winning/losing sides this way. Prove Uncountable set minus a countable set is uncountable Let B be a countable set, and let A be an uncountable set. Prove that A-B is uncountable XGBoost Loss function Approximation With Taylor Expansion As an example, take the objective function of the XGBoost model on the $t$'th iteration:  $$\mathcal{L}^{(t)}=\sum_{i=1}^n\ell(y_i,\hat{y}_i^{(t-1)}+f_t(\mathbf{x}_i))+\Omega(f_t)$$  where $\ell$ is the loss function, $f_t$ is the $t$'th tree output and $\Omega$ is the regularization. One of the (many) key steps for fast calculation is the approximation:  $$\mathcal{L}^{(t)}\approx \sum_{i=1}^n\ell(y_i,\hat{y}_i^{(t-1)})+g_tf_t(\mathbf{x}_i)+\frac{1}{2}h_if_t^2(\mathbf{x}_i)+\Omega(f_t),$$  where $g_i$ and $h_i$ are the first and second derivatives of the loss function.   What I'm asking for is convincing arguments to demystify why the above approximation works:  1) How does XGBoost with the above approximation compare to XGBoost with the full objective function? What potentially interesting, higher-order behavior is lost in the approximation?  2) It's a bit hard to visualize (and depends on the loss function) but, if the loss function has a large cubic component, then the approximation will likely fail. How is it that this doesn't cause problems for XGBoost? In Visual Studio, we've all had "baadf00d", have seen seen "CC" and "CD" when inspecting variables in the debugger in C++ during run-time.  From what I understand, "CC" is in DEBUG mode only to indicate when a memory has been new() or alloc() and unitilialized.  While "CD" represents delete'd or free'd memory.  I've only seen "baadf00d" in RELEASE build (but I may be wrong).  Once in a while, we get into a situation of tacking memory leaks, buffer overflows, etc and these kind of information comes in handy.  Would somebody be kind enough to point out when and in what modes the memory are set to recognizable byte patterns for debugging purpose? Allow bounty to be set with reputation from another site? I'm having a heck of a time trying to disable the option  "Check for updates Automatically"  I ran composer to see what plist was being modified and it looks like ~/Library/Preferences/com.oracle.javadeployment.plist  &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN"    "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt; &lt;plist version="1.0"&gt; &lt;dict&gt;     &lt;key&gt;/com/oracle/javadeployment/&lt;/key&gt;     &lt;dict&gt;         &lt;key&gt;deployment.macosx.check.update&lt;/key&gt;         &lt;string&gt;false&lt;/string&gt; &lt;/dict&gt; &lt;/dict&gt; &lt;/plist&gt;   So I experimented with changing that value to true or false and it would not effect the checkbox under the Java Control Panel > Update > Check for Updates Automatically  Your assistance would be much appreciated.  Initially I was looking @ /Library/Internet\ Plug-Ins/JavaAppletPlugin.plugin