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How to sort a dataframe by multiple column(s)
I want to sort a data.frame by multiple columns. For example, with the data.frame below I would like to sort by column z (descending) then by column b (ascending):
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Programmatically Lighten or Darken a hex color (or rgb, and blend colors)
...unction I was working on to programmatically lighten or darken a hex color by a specific amount. Just pass in a string like "3F6D2A" for the color ( col ) and a base10 integer ( amt ) for the amount to lighten or darken. To darken, pass in a negative number (i.e. -20 ).
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Compare floats in php
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If you do it like this they should be the same. But note that a characteristic of floating-point values is that calculations which seem to result in the same value do not need to actually be identical. So if $a is a literal .17 and $b arrives there through a c...
Type-juggling and (strict) greater/lesser-than comparisons in PHP
...ggling. I must admit it puzzles me, and I'm having a hard time to find out basic logical/fundamental things in comparisons.
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How to add to an existing hash in Ruby
...rds to adding an key => value pair to an existing populated hash in Ruby, I'm in the process of working through Apress' Beginning Ruby and have just finished the hashes chapter.
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How can I sort arrays and data in PHP?
...HP?
How do I sort a complex array in PHP?
How do I sort an array of objects in PHP?
12 Answers
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How to copy Java Collections list
... ArrayList and I want to copy it exactly. I use utility classes when possible on the assumption that someone spent some time making it correct. So naturally, I end up with the Collections class which contains a copy method.
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What does 'super' do in Python?
What's the difference between:
10 Answers
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pandas GroupBy columns with NaN (missing) values
... have a DataFrame with many missing values in columns which I wish to groupby:
9 Answers
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Python: TypeError: cannot concatenate 'str' and 'int' objects [duplicate]
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There are two ways to fix the problem which is caused by the last print statement.
You can assign the result of the str(c) call to c as correctly shown by @jamylak and then concatenate all of the strings, or you can replace the last print simply with this:...