I want to match a file name as "abc (1).xyz" or "abc (2).xyz" or "abc (3).xyz" and so on, in which abc and xyz (extension) is fixed. Besides, the space+(number)  part is optional, i.e. the abc.xyz is also valid.  I have tried the below code, but it didn't returns the success response:  String regex = "abc\\s([0-9])\\.xyz";         Pattern mather = Pattern.compile(regex);          if (mather.matcher(fileName).matches()) {             return true;         } else {             return false;         }   Please suggest any solution for the same. Thanks in advance.
I am tired of always trying to guess, if I should escape special characters like '()[]{}|' etc. when using many implementations of regexps.  It is different with, for example, Python, sed, grep, awk, Perl, rename, Apache, find and so on. Is there any rule set which tells when I should, and when I should not, escape special characters? Does it depend on the regexp type, like PCRE, POSIX or extended regexps?
GeoReference tiff image into the Google map? I want to Geo-reference a tiff image contain a Map for a specific region, I need to add this region(image) and Geo-reference it on the Google map, SO I can see on the map for the region I select the image which I have inserted.  the image also need information such as the Latitude and Longitude of corners and size, and the pixel per meter measurement.  How to do the correct Geo-reference for that ? Another part of my daily  on SE sites.  When viewing a question and it's time to move on, I'll often simply click one of the tags in the question to bring me back to a list of questions with that tag.  This doesn't work in the Android app.  Obligitory screenshot.  I tried to draw a finger that looked like it was tapping a tag, but it ended up looking like, well...  something else, let's say. Wikipedia onebox is dropping random text Random text is getting dropped from Wikipedia oneboxes. See . Screenshot:  This occurs regardless of HTTP/HTTPS and of whether a redirect URL is entered into chat. I initially thought the bug is triggered by &lt;span&gt;s or other HTML formatting elements, but in the Burj Khalifa article's HTML source code, there is no formatting around one of the deleted words. Possibly related to , but this is not specific to numbers. If a car hits a wall at a speed of $v$, and an identical car hits a wall at a speed of $2\,v$, with the kinetic energy equation $E_K = \frac{1}{2}mv^2$ (the speed goes from $v$ to $0$) the second car will lose 4 times the energy, and therefore cause 4 times the damage, but with the force equation $F = ma$ (the car hits the wall and decelerates), it will hit with 2 times the force, and cause 2 times the damage.  How can this be explained? I have a table with a column for ID, Date and Frequency of occurrence for that particular date and ID.  ID    date          Frequency 1     2014-05-18      5 1     2014-05-19      4 1     2014-05-20      25 2     2014-05-20      7 3     2014-05-18      4 3     2014-05-20      1 4     2014-05-18      6   I'm looking to insert the dates for each ID that aren't currently there (assuming that the date ranges from 2014-05-18 to 2014-05-20) and add a value of 0 in Frequency for those.  For example, you can see that  ID 1 has an observation for all three dates;  ID 2 is missing 2014-05-18 and 2014-05-19;   ID 3 is missing 2014-05-19;   ID 4 is missing 2014-05-19 and 2014-05-20.  Therefore, the output should look like this  ID    date          Frequency 1     2014-05-18      5 1     2014-05-19      4 1     2014-05-20      25 2     2014-05-18      0 2     2014-05-19      0 2     2014-05-20      7 3     2014-05-18      4 3     2014-05-19      0 3     2014-05-20      1 4     2014-05-18      6 4     2014-05-19      0 4     2014-05-20      0   I've attempted the following from . However, that will only add dates with 0 Frequency that aren't present throughout the entire table instead of on an ID level.   DECLARE @s DATE = '20140518', @e DATE = '20140520';  SELECT c.date, Frequency = COALESCE(a.Frequency,0) FROM dbo.Calendar AS c LEFT OUTER JOIN dbo.table AS a ON c.date = s.[date] WHERE c.d &gt;= @s AND c.d &lt; DATEADD(DAY, 1, @e); Why do you cast downvotes on answers? This is a question which started off with a , then turned into an , and now it's a question in its own right (as suggested by Jeff). I'm not sure where it could go from here :)  It's obvious that different people cast downvotes for different reasons. (Upvotes are less controversial, generally.) Here are some possible reasons:   Answer is wrong Answer is misleading (may be technically accurate, but will lead to readers making mistakes) Answer doesn't match the question (e.g. a C# answer to a question about Java) Answer doesn't really address the question, e.g. suggesting a completely different solution, even if the question specifies that there are good reasons why the current approach has to be followed Answer is okay, but not as good as another one which currently has fewer votes Answer appears to be plagiarised from existing answers. Answer is by someone I don't like. Answer is abusive (profanity, spam etc). No reason, I just felt like it. I'm a , and prefer down to up. Have you considered down? Ideological grounds: answer suggests a technology I don't like, or expresses a negative opinion of a technology I do like   Personally I go with 1, 2 and 8 - although I'll add comments suggesting changes in various other situations.  Have I missed anything? What do you do, and why? What are the net benefits (to you, the world in general, and the answerer) from your approach? In GLM regression I have always been told to set the reference level of categorical/ordinal/dummy variables to the level with the most exposure (level with most data), because this somehow makes the model more stable. Is there any statistical reason behind this, or just historical practice without statistical reason?  I can understand that one wants a "baselevel" (reference level) in the model that are most likely to be correct, but if you are not sure about the other levels, then they surely should not be included in the regression in the first place? What does {0} mean when found in a string in C#? In a dictionary like this:  Dictionary&lt;string, string&gt; openWith = new Dictionary&lt;string, string&gt;();  openWith.Add("txt", "notepad.exe"); openWith.Add("bmp", "paint.exe"); openWith.Add("dib", "paint.exe"); openWith.Add("rtf", "wordpad.exe");  Console.WriteLine("For key = \"rtf\", value = {0}.", openWith["rtf"]);   The output is:     For Key = "rtf" value = wordpad.exe   What does the {0} mean? Where to ask "subjective and argumentative" questions on programming? Recently  was "closed as subjective and argumentative".  I wonder, where would you recommend to ask such questions? Failed a Reopen Question audit — sure looks like "Not a real question" to me I just failed , which was shown as being closed as "Not a real question".  Seeing as the vote count was positive, I figured it was an audit, but I selected "Leave Closed" anyways because to me     It's difficult to tell what is being asked here.  This question is ambiguous, vague...   There's no code examples, and the phrasing is clunky at best.  This is my second failed audit in two days for difficult questions (first failed audit is , also now closed), so if I get temporarily suspended, it won't be the end of the world (I'll think of it as a forced vacation).    That said, is there a way to dispute these audits?  Or is posting the audit here sufficient? How can magnets be used to pick up pieces of metal when the force from a magnetic field does no work? I learned that the force from a magnetic field does no work. However I was wondering how magnets can be used to pick up pieces of metal like small paperclips and stuff. I also was wondering how magnets can stick to pieces of metal like a refrigerator? bash: syntax error near unexpected token `}' How to copy files via terminal? Why is there a difference between urls submitted to a sitemap and urls in the google index? How to Execute ShortCut From Command line in Windows 7 We came with a scenario where we have to use Shortcut file (.lnk), which is on the desktop, to execute an application for a headless device (i.e, without manual intervention).  Is there any way to execute it from Command prompt? Test if string is a guid without throwing exceptions? Where can I find historical data on flights, specifically Delta international flights?  I need to find out about cancellations, diversions and any other flight data pertaining on particular route at a given time.  This source has to be official and stand up to legal scrutiny. Fixed buffers and interior buffers are not working for a polygon that contains a hole I'm following the online qgis manual available on qgis website. I'm doing the step 21.11.3. ().   To make it simple : I have a raster converted to vector, so now it is a polygon (several polygons). I'm doing an interior buffer exactly how it is described in the manual. I didn't obtain the same result. I can see the interior buffer just in some polygons, not in all of them ->    The interior buffers appear just for those polygons, that don't contain a hole. I use qgis 2.18.3.  This is how i created the interior buffer ->    In green you see the input layer : suitable_terrain, in blue the output layer, the interior buffer.   It is not a problem of a projection. I use WGS84 UTM Zone 34S where the units are in meters. I did also the Check validity and i obtain the same result. Probability question of hats How does the Adam method of stochastic gradient descent work?