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Convert columns to string in Pandas
...taFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save this to, along with some other options...
...
Naming returned columns in Pandas aggregate function? [duplicate]
...
107
This will drop the outermost level from the hierarchical column index:
df = data.groupby(...)....
Finding duplicates in O(n) time and O(1) space
Input: Given an array of n elements which contains elements from 0 to n-1, with any of these numbers appearing any number of times.
...
Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)
...
+100
What I did was creating my own Window and Style. Because I like to have control over everything and I didn't want some external libra...
How do I find out if first character of a string is a number?
...
260
Character.isDigit(string.charAt(0))
Note that this will allow any Unicode digit, not just 0-9....
Simple Digit Recognition OCR in OpenCV-Python
...r in box.
Once corresponding digit key is pressed, it resizes this box to 10x10 and saves 100 pixel values in an array (here, samples) and corresponding manually entered digit in another array(here, responses).
Then save both the arrays in separate txt files.
At the end of manual classification of...
Tools for analyzing performance of a Haskell program
...oblem.
Run your program with +RTS -s
$ time ./A +RTS -s
./A +RTS -s
749700
9,961,432,992 bytes allocated in the heap
2,463,072 bytes copied during GC
29,200 bytes maximum residency (1 sample(s))
187,336 bytes maximum slop
**2 MB** total memory in use (0...
Delete first character of a string in Javascript
...ant to delete the first character of a string, if the first character is a 0. The 0 can be there more than once.
14 Answer...
Extract elements of list at odd positions
...l. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation
The [1::2] at the end is just a notation for list slicing. Usually it is in the followi...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...ntents of True. In other words, True is reassignable:
Python 2.7 (r27:82508, Jul 3 2010, 21:12:11)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> True = 4
>>> True
4
In Python 3.x it truly becomes a k...
