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Pandas - How to flatten a hierarchical index in columns

...et the columns to the top level: df.columns = df.columns.get_level_values(0) Note: if the to level has a name you can also access it by this, rather than 0. . If you want to combine/join your MultiIndex into one Index (assuming you have just string entries in your columns) you could: df.column...
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What's the best way to send a signal to all members of a process group?

... 308 You don't say if the tree you want to kill is a single process group. (This is often the case ...
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How to print a number with commas as thousands separators in JavaScript

... ====>"} ${x} => ${result}`); return pass; } let failures = 0; failures += !test(0, "0"); failures += !test(100, "100"); failures += !test(1000, "1,000"); failures += !test(10000, "10,000"); failures += !test(100000, "100,000"); failures += !test(1000000, "...
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What do hjust and vjust do when making a plot using ggplot?

... The value of hjust and vjust are only defined between 0 and 1: 0 means left-justified 1 means right-justified Source: ggplot2, Hadley Wickham, page 196 (Yes, I know that in most cases you can use it beyond this range, but don't expect it to behave in any specific way. This...
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How to get the source directory of a Bash script from within the script itself?

... #!/bin/bash DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )" is a useful one-liner which will give you the full directory name of the script no matter where it is being called from. It will work as long as the last component of the p...
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Animation CSS3: display + opacity

...:hover .child { display: block; -webkit-animation: fadeInFromNone 0.5s ease-out; -moz-animation: fadeInFromNone 0.5s ease-out; -o-animation: fadeInFromNone 0.5s ease-out; animation: fadeInFromNone 0.5s ease-out; } @-webkit-keyframes fadeInFromNone { 0% { display: no...
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Why must a nonlinear activation function be used in a backpropagation neural network? [closed]

... 170 The purpose of the activation function is to introduce non-linearity into the network in turn, ...
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What is the fastest integer division supporting division by zero no matter what the result is?

... 107 Inspired by some of the comments I got rid of the branch on my Pentium and gcc compiler using ...
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Find integer index of rows with NaN in pandas dataframe

...MultiIndex that you can use to index back into df, e.g.: df['a'].ix[index[0]] >>> 1.452354 For the integer index: df_index = df.index.values.tolist() [df_index.index(i) for i in index] >>> [3, 6] share...
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How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?

...conds with'%Q tho. – Mini John Feb 10 '15 at 2:13 3 To follow up on @TheMiniJohn's answer. It loo...