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How to drop rows of Pandas DataFrame whose value in a certain column is NaN
...ta, including dropna(), is built into pandas explicitly. Aside from potentially improved performance over doing it manually, these functions also come with a variety of options which may be useful.
In [24]: df = pd.DataFrame(np.random.randn(10,3))
In [25]: df.iloc[::2,0] = np.nan; df.iloc[::4,1] ...
How do I use LINQ Contains(string[]) instead of Contains(string)
...ght, but you need to create a List<string> from string[] first. Actually a List<int> would be better if uid is also int. List<T> supports Contains(). Doing uid.ToString().Contains(string[]) would imply that the uid as a string contains all of the values of the array as a substr...
Sublime Text 2: Trim trailing white space on demand
...ing spaces and delete them in a flash.
ST2 provides a way to automatically delete trailing spaces upon file
save. Depending on your settings, it may be more handy to just
highlight them and/or delete them by hand. This plugin provides just
that!
Usage: click "Edit / Trailing Spaces / De...
How I can delete in VIM all text from current line to end of file?
...
:.,$d
This will delete all content from current line to end of the file. This is very useful when you're dealing with test vector generation or stripping.
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Reference alias (calculated in SELECT) in WHERE clause
...probably consider a computed column (and perhaps persisted) instead, especially if a lot of queries refer to this same expression.
PS your fears seem unfounded. In this simple example at least, SQL Server is smart enough to only perform the calculation once, even though you've referenced it twice. ...
How to loop through files matching wildcard in batch file
... 'f.out'. I want to write a batch file (in Windows XP) which goes through all the filenames, for each one it should:
7 Ans...
Change EOL on multiple files in one go
...n Notepad++ (or even with another tool) to change the line ending automatically on multiple files in one go ?
7 Answers
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How to iterate over arguments in a Bash script
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Use "$@" to represent all the arguments:
for var in "$@"
do
echo "$var"
done
This will iterate over each argument and print it out on a separate line. $@ behaves like $* except that when quoted the arguments are broken up properly if there...
.htaccess not working apache
... have a server from AWS EC2 service running on Linux ubuntu and I have installed apache, php, and mysql.
12 Answers
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Favicon: .ico or .png / correct tags? [duplicate]
...icon format do you recommend and why? I want it to be supported by IE7 and all the modern browsers.
3 Answers
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