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How to check if a column exists in Pandas
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To check if one or more columns all exist, you can use set.issubset, as in:
if set(['A','C']).issubset(df.columns):
df['sum'] = df['A'] + df['C']
As @brianpck points out in a comment, set([]) can alternatively be constructed with curly...
vim repeat find next character 'x'
... and ;), to a different character than the repetition of an edit (.). This allows you to do fast searches and changes to the search results. If you want to replace some + in a line with * you could do something like this (skipping some characters and replacing others): f+r*;.;;.;.;;;.
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Best way to make Django's login_required the default
...p, the vast majority of which requires a login to access. This means that all throughout our app we've sprinkled:
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How to access outer class from an inner class?
...d Jan 7 '10 at 23:54
Daniel VassalloDaniel Vassallo
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How do I enable language extensions from within GHCi?
... -XRankNTypes. The -X part is a compiler switch, by the way, extension is called just RankNTypes.
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What is a tracking branch?
...acking Branches
Checking out a local branch from a remote branch automatically creates what is called a tracking branch. Tracking branches are local branches that have a direct relationship to a remote branch. If you’re on a tracking branch and type git push, Git automatically knows which server ...
What is Castle Windsor, and why should I care?
... COUPLING that is hard to change. (this is a tiny contrived example after all)
So what if, instead of newing this bad boy up inside WorkflowStepper, you just passed it into the constructor?
So then whoever called it had to new up the EmailSender.
new WorkflowStepper(emailSender).Step()
Imagine you ...
Capture keyboardinterrupt in Python without try-except
...re some way in Python to capture KeyboardInterrupt event without putting all the code inside a try - except statement?
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'parent.relativePath' points at my com.mycompany:MyProject instead of org.apache:apache - Why?
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Warnings don't come falling out of the skies. There's a reason for it. Adding an empty <relativePath></relativePath> without knowing why isn't a solution....
– Lawrence
Apr 20 '14 at 19:16
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Difference between Big-O and Little-O Notation
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f ∈ O(g) says, essentially
For at least one choice of a constant k > 0, you can find a constant a such that the inequality 0 <= f(x) <= k g(x) holds for all x > a.
Note that O(g) is the set of all functions for which this condit...