/etc/sudoers had been deleted, and I wanted to restore the default file from the package. I tried:  apt-get install sudo apt-get install --reinstall sudo apt-get remove sudo &amp;&amp; apt-get install sudo  None of which worked but all of which warned about /etc/sudoers not existing.  In the end I did apt download sudo &amp;&amp; ar xv sudo &amp;&amp; tar xf data.tar.xz ./etc/sudoers and just copied that file to /etc/sudoers, but was there a more straightforward way to restore the file?
After trying to delete apache and tomcat, and now trying to reinstall apache 2, I am missing the init.d/apache2 file to start/stop my server.  I am not sure if the new install actualy worked, and my apt-get purge apache2 didn't remove everything in the first place!  How can I get the init.d/apache2 file to test if server starts / is installed properly (I had removed files and directories manually)?
Where is it preferred to place the answer to duplicate questions? How to find the real user home directory using python? Using "the" instead of "a" for something that isn't a specific object I've been curious about this for a while.  Generally, one uses "the" if they mean a specific object ("The copy of Lord of the Rings I bought yesterday") instead of any object that fits a description ("I have a copy of Lord of the Rings").  However I've seen "the" used in some cases where the phrase doesn't refer to a specific object. I've noticed it mostly being about technology, such as "This game requires the Classic Controller" (seen on some Wii Virtual Console games). While saying "This game requires a Classic Controller" seems to be correct as well, using "the" doesn't feel wrong either.  The controller's page on Wikipedia also uses "the":   What is the rule that allows the use of "the" in this context?  I presume it has something to do with "Classic Controller" being a proper noun. How do I remove hidden backup files? I have files ending in ~ in my home directory, and I want to delete them. How do I do that? How do I prevent this backup functionality? Is there a way to do the following using LINQ?  foreach (var c in collection) {     c.PropertyToSet = value; }   To clarify, I want to iterate through each object in a collection and then update a property on each object.  My use case is I have a bunch of comments on a blog post, and I want to iterate through each comment on a blog post and set the datetime on the blog post to be +10 hours. I could do it in SQL, but I want to keep it in the business layer. I'm trying to do raster algebra with two rasters, but when I transform the rasters to array I can't do the operation because the files do not have the same extent  example:  from osgeo import gdal import numpy as np  IMG1 = gdal.Open('C:/IMG1.TIF') IMG2 = gdal.Open('C:/IMG2.TIF')  img1 = IMG1.ReadAsArray() img2 = IMG2.ReadAsArray()  img1+img2 &gt;&gt;&gt;&gt;&gt; ValueError: operands could not be broadcast together with shapes (5353,3352) (5548,3232)    So.. if I see the gt of every img show that img1 and img2 have the same size of the pixel (100) but different extent  g1 = IMG1.GetGeoTransform() gt1 &gt;&gt;&gt;&gt;&gt; (482084.999999999, 100.0, 0.0, 5652715.00001374, 0.0, -100.0) g2 = IMG2.GetGeoTransform() gt2 &gt;&gt;&gt;&gt;&gt; (475184.999999999, 100.0, 0.0, 5643715.00001535, 0.0, -100.0)   So.. I used this operation in order to get the intersect extent.. but I don't know how to apply  r1 = [gt1[0], gt1[3],gt1[0] + (gt1[1] * IMG1.RasterXSize), gt1[3] + (gt1[5] * IMG1.RasterYSize)] r2 = [gt2[0], gt2[3],gt2[0] + (gt2[1] * IMG2.RasterXSize), gt2[3] + (gt2[5] * IMG2.RasterYSize)] intersection = [max(r1[0], r2[0]), min(r1[1], r2[1]), min(r1[2], r2[2]), max(r1[3], r2[3])] ARIMA equation interpretation I'm trying to replicate ARIMA (1,0,1)(1,0,1) equation in excel as a formula but I am not able to understand the interpretation of white noise residual e(t) or u(t).If could help me understand the interpretation and how to derive it from raw data it'll be really great.  Thanks Taskbar > File Explorer > Context Menu failing me So I have the latest version of Windows 10, and this is a new PC.  File Explorer is in the taskbar.  When I open the context menu (right-click) on it, I get the list of folders as seen in the picture.  When I right click on any of them, I get the blank black box you see in the picture.  If I click on any of the folders, such as Downloads or Update.  Nothing happens.  They don't open.  The only way to use it is to click on the actual File Explorer icon and then navigate from there.  I've tried uninstalling things (not that I have much installed since it's a fresh install) and I've tried scans, etc.  This only happens with File Explorer.  Everything else works fine.  I can't figure it out. SQL - Stored Procedure with Select Statement using IN (@Variable_CommaDelimitedListOfIDS) Extra blue line appearing in the top bar (Firefox only) Whenever we click on the Inbox or the Achievements in the top bar, an extra blue line appears near by them. This is reproducible on Stack Overflow and Anime &amp; Manga(as I use only those) but not on Meta Stack Overflow. Here is a snapshot of that.    I'm using Firefox 25.0.1 on Win7 Pro.  Edit: Just to be double sure, I restarted the FF and still I'm able to see it. Here is another snapshot, with the 2 distinct sites. From A Classical Introduction to Modern Number Theory by Ireland and Rosen, page 33:     Corollary 1 (Euler's Theorem). If $(a,m) = 1$, then $a^{\phi(m)} \equiv 1\,(m)$.      Proof. The units in $\mathbb{Z}/m\mathbb{Z}$ form a group of order $\phi(m)$. If $(a,m) = 1$, $\bar{a}$ is a unit. Thus $\bar{a}^{\phi(m)} = \bar{1}$ or $a^{\phi(m)} \equiv 1\,(m)$.   If I'm interpreting this correctly, this proof implicitly uses the fact(?) that if $G$ is a group and $x\in G$, then $x^{|G|}=1$, where $1$ is the identity element of $G$.  If this is indeed true, can someone explain why? (I have had no prior exposure to group theory.) Here is a simple table.  I want to merge 4 cells. I want to combine the three "this" cells area in this table. I thought I have to use multirow and multicolum at same time. However, I could not find how to use it.  If possible, could you post the modified LaTeX source code?     My LaTeX code:  \documentclass{article} \usepackage{multirow}% http://ctan.org/pkg/multirow \usepackage{hhline}% http://ctan.org/pkg/hhline \begin{document}  \begin{table}[ph] \begin{center} \begin{tabular}{c|c|c|c|c} \hline \multirow{2}{*}{Raaa (k)} &amp; \multicolumn{4}{c}{C ()} \\ \hhline{~----}  &amp; 3.3 &amp; 2.5 &amp; 1 &amp; 0.5 \\ \hline \multirow{2}{*}{Raaa (k)} &amp; \multirow{2}{*}{this} &amp; this &amp; 0.5 &amp; 0.6\\ \hhline{~~~--}            &amp;                       &amp; this &amp; 0.7 &amp; 1.2 \\ \hline \end{tabular} \caption{R, C ripple size} \label{T:peak} \end{center} \end{table} \end{document} What size breaker and wire do I need to run 2 GFCI receptacles and a flood light on exterior of my house? Is it OK to use a 15amp breaker and a 14ga wire (14/2 copper) to run 2 GFCI receptacles and a flood light on the exterior of my home? The voltage is 120.  The 2 receptacles are rated at 15amps and won't be carrying a continuous load very often. Might plug a George foreman grill into it every now and then, maybe some party lights. And an occasional power tool (hedge trimmers, weed eater, etc.). I believe the flood lights are 75w a piece.  Should I go with a 20amp/12ga wire instead?  Update**  It is a new circuit so I think I will go with the 20A/12ga just to be safe and I will check the code requirements for having receptacles on the same circuits as lights!  Lets just it is OK to have both receptacles and lights on the same circuit. Is this an acceptable way to wire it? Using a junction box to divert wire towards the outlets and a separate wire to control the flood light with a switch on the same circuit? Pardon my drawing! Pass extra parameters to an event handler? Map not loading when using getLegend and showing error for getView() I was able to run my application on using Legend earlier but now I want to update my Legend when scrolling on the map. So I tried to used this code  . And I got the gist of how he is able to do that but when I am trying the same I keeping getting the error var graphicUrl = wmsSource.getLegendUrl(currentResolution);  I think this is mainly due to the wmsSource not declare. But I tried to initialize  seems wmsSource in TileWMS but does not seems to work. var getExtent = function () {     return map.getView().calculateExtent(); } var getProjectionCode = function () {     return map.getView().getProjection().getCode(); }  var updateLegend = function() {     var currentResolution = map.getView().getResolution();     var graphicUrl = wmsSource.getLegendUrl(currentResolution);        const crs = `&amp;CRS=${getProjectionCode()}`;     const bbox = `&amp;BBOX=${getExtent().join(',')}`;     const height = getHeight(getExtent());     const width = getWidth(getExtent());     const heightAndWidth = `&amp;srcwidth=${height}&amp;srcheight=${width}` ;     const legenOptions = &quot;&amp;legend_options=countMatched:true;fontAntiAliasing:true;hideEmptyRules:true;forceLabels:on&quot; ;        var img = document.getElementById('legend');     img.src = `${graphicUrl}${crs}${bbox}${heightAndWidth}${legenOptions}`; }; //Updated Legend End   //View var myview = new ol.View({     center : [8717490.201868,2788422.791843],     zoom : 4 })  var firstSel = document.getElementById(&quot;City&quot;); var secSel = document.getElementById(&quot;Sector&quot;);  //var LayerArray = [baseLayer, firstLayer]  //Map var map = new ol.Map({       target : 'mymap',       view: myview,       layers: [         new ol.layer.Tile({             source : new ol.source.OSM({                 attributions: 'Surveyor Allpication'             })         }),         new ol.layer.Tile({             source : new ol.source.TileWMS({                url: 'http://localhost:8089/geoserver/India/wms',                params: {'LAYERS': 'India:India', 'TILED': true,'TRANSPARENT':true},                ratio: 1,                serverType: 'geoserver',                transition: 0,             })         })       ] }) updateLegend();   This here is my JS &lt;div class=&quot;innerMap&quot;&gt;     &lt;div class=&quot;map&quot; id=&quot;mymap&quot;&gt;&lt;/div&gt;         Legend:     &lt;div&gt;&lt;img id=&quot;legend&quot;/&gt;&lt;/div&gt;     &lt;!--    &lt;div&gt;&lt;img src=&quot;http://localhost:8089/geoserver/wms?REQUEST=GetLegendGraphic&amp;VERSION=1.0.0&amp;FORMAT=image/png&amp;WIDTH=20&amp;HEIGHT=20&amp;LAYER=India%3AIndia&amp;RULE=Agra&quot; /&gt;%Name&lt;/div&gt; --&gt; &lt;!--    &lt;div&gt;&lt;img src=&quot;http://localhost:8089/geoserver/India/wms?SERVICE=WMS&amp;VERSION=1.1.1&amp;REQUEST=GetLegendGraphic&amp;FORMAT=image/png&amp;WIDTH=20&amp;HEIGHT=20&amp;LAYER=India%3AIndia&amp;SRS=EPSG%3A4326&amp;STYLES=&amp;SRCWIDTH=742&amp;SRCHEIGHT=768&amp;BBOX=75.4541015625%2C14.21630859375%2C91.7578125%2C31.09130859375&amp;LEGEND_OPTIONS=countMatched:true;fontAntiAliasing:true;hideEmptyRules:true&quot; /&gt; &lt;/div&gt;  --&gt;     &lt;/div&gt;  This is my HTML. How do I make this work? how to calculate $\int_C \frac{2xy^2dx-2yx^2dy}{x^2+y^2}$ using green theorm or directly Calculate $$\int_C \frac{2xy^2dx-2yx^2dy}{x^2+y^2},$$ where $C$ is the ellipse $3x^2 +5y^2 = 1$ taken in the positive direction.   I tried to calculate the integral using green theorm.  now i need to build enclosier that doesn't enclose $(0,0)$ i am having hard time guessing what to build.  a circle and ellipse might be perfect but then the domain is not easy to write. can i have hint please ? I have a string that contains both double-quotes and backslashes that I want to set to a variable in Python. However, whenever I try to set it, the quotes or slashes are either removed or escaped. Here's an example:  &gt;&gt;&gt; foo = 'baz "\"' &gt;&gt;&gt; foo 'baz ""'   So instead of baz "\" like I want I'm getting baz "". If I then try to escape the backslash, it doesn't help either:  &gt;&gt;&gt; foo = 'baz "\\"' &gt;&gt;&gt; foo 'baz "\\"'   Which now matches what I put in but wasn't what I originally wanted. How do you get around this problem? Changing back button in iOS 7 disables swipe to navigate back How to convert a std::string to const char* or char* Should flagging a question for closure prevent close-voting? Back in April, I flagged a post as "not a real question".  The post was subsequently closed and reopened, then closed again and finally just reopened a 2nd time a short time ago.  I still firmly believe the post is not acceptable for SO, so I went to use my recently acquired close vote privilege and was greeted with the following messsage:    I specifically clicked close and not flag (and figuring I just clicked in error, I tried again and got the same message).  I do understand that, in the new closing system, flagging for closure is treated very much like a close vote (since it throws it to the close vote queue) except no vote is actually recorded.  My issue is why should by flag be counted as a close vote when I never actually voted to close.