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How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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How do I declare a global variable in VBA?
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When I try to declare an array as public it says: array and user-defined data types can't be declared as public.
– kapilddit
Nov 13 '19 at 12:25
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Java Generics Wildcarding With Multiple Classes
...object, but I want to force whatever class it represents to extend class A and implement interface B.
3 Answers
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Determine installed PowerShell version
How can I determine what version of PowerShell is installed on a computer, and indeed if it is installed at all?
19 Answers...
DistutilsOptionError: must supply either home or prefix/exec-prefix — not both
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Are you using OS X and Homebrew? The Homebrew python page https://github.com/Homebrew/brew/blob/master/docs/Homebrew-and-Python.md calls out a known issue with pip and a work around.
Worked for me.
You can make this "empty prefix" the def...
What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and be
It seems that many projects slowly come upon a need to do matrix math, and fall into the trap of first building some vector classes and slowly adding in functionality until they get caught building a half-assed custom linear algebra library, and depending on it.
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What's the best way to convert a number to a string in JavaScript? [closed]
...he only conceivable: the number does not care nor know how it was entered, and the standard printed representation is with exactly one digit before the dot.
– Svante
Sep 2 '15 at 18:32
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open read and close a file in 1 line of code
...lose it for various reasons.
So, what you can do to keep it short, simple and explicit:
with open('pagehead.section.htm','r') as f:
output = f.read()
Now it's just two lines and pretty readable, I think.
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Any implementation of Ordered Set in Java?
...Objective-C there is a collection called NSOrderedSet that acts as Set and its items can be accessed as an Array 's ones.
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Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
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Since С99 the matching between format specifiers and floating-point argument types in C is consistent between printf and scanf. It is
%f for float
%lf for double
%Lf for long double
It just so happens that when arguments of type float are passed as variadic parameters,...