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How to check if a column exists in Pandas
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This will work:
if 'A' in df:
But for clarity, I'd probably write it as:
if 'A' in df.columns:
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Check if bash variable equals 0 [duplicate]
... the variables into the expression. The problem here is that the -eq operator is incorrectly used as an operator with only one argument (the zero), but it requires two arguments. That is why you get the unary operator error message.
EDIT: As Doktor J mentioned in his comment to this answer, a safe ...
Commonly accepted best practices around code organization in JavaScript [closed]
As JavaScript frameworks like jQuery make client side web applications richer and more functional, I've started to notice one problem...
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How do I execute code AFTER a form has loaded?
In .NET, Windows Forms have an event that fires before the Form is loaded (Form.Load), but there is no corresponding event that is fired AFTER the form has loaded. I would like to execute some logic after the form has loaded.
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How to print a date in a regular format?
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The WHY: dates are objects
In Python, dates are objects. Therefore, when you manipulate them, you manipulate objects, not strings or timestamps.
Any object in Python has TWO string representations:
The regular representation that is used by print can be get using the str() function. It ...
Guards vs. if-then-else vs. cases in Haskell
...nt, all three versions are equivalent.
That being said, my rule of thumb for styles is that if you can read it as if it was English (read | as "when", | otherwise as "otherwise" and = as "is" or "be"), you're probably doing something right.
if..then..else is for when you have one binary condition,...
AngularJS $http and $resource
I have some web services that I want to call. $resource or $http , which one should I use?
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What is a StoryBoard ID and how can i use this?
i'm new to IOS developing and recently started in Xcode 4.5. I saw for every viewController that i could set some identity variables including the storyboard ID. What is this and how can i use it?
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Java: Static vs inner class [duplicate]
...esting instance, so a static nested class cannot invoke non-static methods or access non-static fields of an instance of the class within which it is nested.
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Alternative timestamping services for Authenticode
We perform code signing and timestamping for all our production builds. Occasionally (usually when we are about to RTM (!)) the timestamp server at Verisign (" http://timestamp.verisign.com/scripts/timstamp.dll ") decides to go offline intermittently.
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