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Split (explode) pandas dataframe string entry to separate rows
I have a pandas dataframe in which one column of text strings contains comma-separated values. I want to split each CSV field and create a new row per entry (assume that CSV are clean and need only be split on ','). For example, a should become b :
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How to swap keys and values in a hash
How do I swap keys and values in a Hash?
6 Answers
6
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How to check if PHP array is associative or sequential?
PHP treats all arrays as associative, so there aren't any built in functions. Can anyone recommend a fairly efficient way to check if an array contains only numeric keys?
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Retain precision with double in Java
The above code prints:
22 Answers
22
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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
I have the following 2 data.frames:
13 Answers
13
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Why is there no logical xor in JavaScript?
Why is there no logical xor in JavaScript?
19 Answers
19
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Creating dataframe from a dictionary where entries have different lengths
Say I have a dictionary with 10 key-value pairs. Each entry holds a numpy array. However, the length of the array is not the same for all of them.
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Regex lookahead, lookbehind and atomic groups
I found these things in my regex body but I haven't got a clue what I can use them for.
Does somebody have examples so I can try to understand how they work?
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How do you perform a left outer join using linq extension methods
Assuming I have a left outer join as such:
7 Answers
7
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When is “i += x” different from “i = i + x” in Python?
I was told that += can have different effects than the standard notation of i = i + . Is there a case in which i += 1 would be different from i = i + 1 ?
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