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How to round up to the nearest 10 (or 100 or X)?
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11 Answers
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How to swap keys and values in a hash
...was inverted (in essence, by letting you access keys through values):
{a: 1, b: 2, c: 3}.key(1)
=> :a
If you want to keep the inverted hash, then Hash#invert should work for most situations:
{a: 1, b: 2, c: 3}.invert
=> {1=>:a, 2=>:b, 3=>:c}
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If you have duplicate values,...
Combining two Series into a DataFrame in pandas
I have two Series s1 and s2 with the same (non-consecutive) indices. How do I combine s1 and s2 to being two columns in a DataFrame and keep one of the indices as a third column?
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What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
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581
They take up different amounts of space and they have different ranges of acceptable values.
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How to get the first column of a pandas DataFrame as a Series?
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143
>>> import pandas as pd
>>> df = pd.DataFrame({'x' : [1, 2, 3, 4], 'y' : [4,...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
I knew boolean in mysql as tinyint (1) .
4 Answers
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No secret option provided to Rack::Session::Cookie warning?
I am running Rails 3.2.3, Ruby 1.9 under Fedora 17. I get this warning, when I run rails s , and how do I fix?
7 Answers
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Remove columns from dataframe where ALL values are NA
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12 Answers
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