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Combine two columns of text in pandas dataframe
I have a 20 x 4000 dataframe in Python using pandas. Two of these columns are named Year and quarter . I'd like to create a variable called period that makes Year = 2000 and quarter= q2 into 2000q2 .
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How to insert tab character when expandtab option is on in Vim
When I'm in insert mode and I have the expandtab option switched on, pressing Tab ↹ results in inserting the configured number of spaces.
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SecurityException: Permission denied (missing INTERNET permission?)
this error is really really really strange and I don't know how to reproduce it and how to fix it because I made a lot of searches but nothing was useful.
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Why is Java's SimpleDateFormat not thread-safe? [duplicate]
... SimpleDateFormat.
For example parse(..) calls calendar.clear() initially and then calendar.add(..). If another thread invokes parse(..) before the completion of the first invocation, it will clear the calendar, but the other invocation will expect it to be populated with intermediate results of th...
How can I use goto in Javascript?
...led Summer of Goto that allows you use JavaScript at its fullest potential and will revolutionize the way you can write your code.
This JavaScript preprocessing tool allows you to create a label and then goto it using this syntax:
[lbl] <label-name>
goto <label-name>
For example, the ex...
What does java.lang.Thread.interrupt() do?
.... Then code running in that target thread MAY poll the interrupted status and handle it appropriately. Some methods that block such as Object.wait() may consume the interrupted status immediately and throw an appropriate exception (usually InterruptedException)
Interruption in Java is not pre-emp...
Return all enumerables with yield return at once; without looping through
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It's definitely not a stupid question, and it's something that F# supports with yield! for a whole collection vs yield for a single item. (That can be very useful in terms of tail recursion...)
Unfortunately it's not supported in C#.
However, if you have several...
Mercurial (hg) commit only certain files
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You can specify the files on the command line, as tonfa writes:
$ hg commit foo.c foo.h dir/
That just works and that's what I do all the time. You can also use the --include flag that you've found, and you can use it several times like this:
$ hg commit -I ...
CentOS+Nginx+PHP+MySQL详细配置(图解) - PHP - 清泛IT论坛，有思想、有深度
本帖最后由 zqp2013 于 2015-4-26 14:29 编辑
一、安装MySQL
        目前web服务器已经很少有跑静态页面的，如果要跑动态网站那当然就离不开数据库，虽然在以前文章中有写MySQL是怎么安装的，但是感觉好久没...
Visual Studio Editor does not underline errors anymore
... or the MVC Beta (which I guess is unlikely). Furthermore have I installed and uninstalled both CodeRush and Resharper for evaluation purposes (decided not to keep either one of them).
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