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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...
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...
...
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...
Rails I18n validation deprecation warning
I just updated to rails 4.0.2 and I'm getting this warning:
5 Answers
5
...
How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
...ns:
- Range.
E.g. a-z matches an lower case letters from a to z
E.g. 0-5 matches any number from 0 to 5
[] Match exactly one of the objects inside these brackets.
E.g. [a] matches the letter a
E.g. [abc] matches a single letter which can be a, b or c
E.g. [a-z] matches any single lower cas...
How to filter Pandas dataframe using 'in' and 'not in' like in SQL
...where)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to_keep
['UK', 'China']
>>> df.country.isin(countries_to_keep)
0 False
1 True
2 False
3 True
Name: country, dtype: bool
>>>...
How should I validate an e-mail address?
...am", as will org.apache.commons.validator.routines.EmailValidator)
(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0...
Limit Decimal Places in Android EditText
...
120
More elegant way would be using a regular expression ( regex ) as follows:
public class Decimal...
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...