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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
I am working with the pandas library and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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Library not loaded: /usr/local/opt/readline/lib/libreadline.6.2.dylib
I just installed posgresql with homebrew and when I go on to type the command
22 Answers
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C++ templates Turing-complete?
I'm told that the template system in C++ is Turing-complete at compile time. This is mentioned in this post and also on wikipedia .
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Placing border inside of div and not on its edge
I have a <div> element and I want to put a border on it. I know I can write style="border: 1px solid black" , but this adds 2px to either side of the div, which is not what I want.
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Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
After conducting some experiments on square matrices of different sizes, a pattern came up. Invariably, transposing a matrix of size 2^n is slower than transposing one of size 2^n+1 . For small values of n , the difference is not major.
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C# short/long/int literal format?
In C / C# / etc. you can tell the compiler that a literal number is not what it appears to be (ie., float instead of double , unsigned long instead of int :
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How to detect IE11?
When I want to detect IE I use this code:
15 Answers
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Sorting a set of values [closed]
I have values like this:
1 Answer
1
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UIView frame, bounds and center
I would like to know how to use these properties in the right manner.
6 Answers
6
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How to define a function in ghci across multiple lines?
I'm trying to define any simple function that spans multiple lines in ghci, take the following as an example:
7 Answers
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