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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
How can I achieve the equivalents of SQL's IN and NOT IN ?
9 Answers
9
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How do I compute derivative using Numpy?
...mbolic Differentiation
Compute derivatives by hand.
Finite differences require no external tools but are prone to numerical error and, if you're in a multivariate situation, can take a while.
Symbolic differentiation is ideal if your problem is simple enough. Symbolic methods are getting quite r...
What is the easiest way to duplicate an activerecord record?
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Does this still work in Rails 3.1.0.beta? When I do q = p.clone, and then p == q, I get true back. On the other hand, if I use q = p.dup, I get false back when comparing them.
– Juno Woods
Feb 8 '11 at 2:10
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Bash tool to get nth line from a file
...tail will be slow for a huge file. I would suggest sed like this:
sed 'NUMq;d' file
Where NUM is the number of the line you want to print; so, for example, sed '10q;d' file to print the 10th line of file.
Explanation:
NUMq will quit immediately when the line number is NUM.
d will delete the li...
Don't display pushd/popd stack across several bash scripts (quiet pushd/popd)
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@xdevs23 || exit $? is equivalent to just || exit. Same for return.
– user4642212
Aug 23 at 17:51
1
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What's the difference between EscapeUriString and EscapeDataString?
...f I'm not escaping a whole URI but only part of it -- (i.e. the data for a query string parameter)? Am I escaping data for the URI, or does EscapeDataString imply something completely different?
– BrainSlugs83
Nov 10 '13 at 3:37
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What order are the Junit @Before/@After called?
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So instead of quoting the somewhat ambiguous documentation, can you please explain it in your own words? Are @Before and @After methods run before every other class method (once per method), or just before and after the entire suite of cla...
AngularJS : Initialize service with asynchronous data
...ontroller, if you don't want this you could create a new promise with the $q service
return MyService.promise;
}
}})
}):
Your controller won't get instantiated before all dependencies are resolved:
app.controller('MainCtrl', function($scope,MyService) {
console.log('Promise ...
How to grant permission to users for a directory using command line in Windows?
... error about "OI not recognized". Solution: Put the user+perms argument in quotes. For example: C:\>icacls "D:\test" /grant "John:(OI)(CI)F" /T
– JDS
Jan 8 '18 at 16:56
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How to identify whether a file is normal file or directory
...n [3]: p.is_file()
Out[3]: False
In [4]: p.is_dir()
Out[4]: True
In [5]: q = p / 'bin' / 'vim'
In [6]: q.is_file()
Out[6]: True
In [7]: q.is_dir()
Out[7]: False
Pathlib is also available on Python 2.7 via the pathlib2 module on PyPi.
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