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How can I time a code segment for testing performance with Pythons timeit?
...Focus on one specific thing. Disk I/O is slow, so I'd take that out of the test if all you are going to tweak is the database query.
And if you need to time your database execution, look for database tools instead, like asking for the query plan, and note that performance varies not only with the e...
How to use performSelector:withObject:afterDelay: with primitive types in Cocoa?
...e 0 or 1. It is true that most code won't care and will simply do an if () test on it, but it is conceivable that some code will depend on it being 0 or 1, and thus won't treat some large address value as being the same as 1 (YES).
– user102008
Oct 21 '11 at 22...
GroupBy pandas DataFrame and select most common value
...re's also an additional solution that supports multiple modes.
On a scale test that's representative of the data I'm working with, this reduced runtime from 37.4s to 0.5s!
Here's the code for the solution, some example usage, and the scale test:
import numpy as np
import pandas as pd
import rando...
Warning message: In `…` : invalid factor level, NA generated
...or numeric values)
# (as.vector can be use for objects - not tested)
fixed$Type <- as.character(fixed$Type)
fixed[1, ] <- c("lunch", 100)
# Re-factorize with the as.factor function or simple factor(fixed$Type)
fixed$Type <- as.factor(fixed$Type)
...
How to output something in PowerShell
... outputting something is PowerShell is a thing of beauty - and one its greatest strengths. For example, the common Hello, World! application is reduced to a single line:
"Hello, World!"
It creates a string object, assigns the aforementioned value, and being the last item on the command pipeline i...
How do I create a file AND any folders, if the folders don't exist?
...ine I wish to create (or overwrite) the following file :- C:\Temp\Bar\Foo\Test.txt
9 Answers
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Import error: No module name urllib2
...
For a script working with Python 2 (tested versions 2.7.3 and 2.6.8) and Python 3 (3.2.3 and 3.3.2+) try:
#! /usr/bin/env python
try:
# For Python 3.0 and later
from urllib.request import urlopen
except ImportError:
# Fall back to Python 2's urlli...
Do NSUserDefaults persist through an Update to an app in the Appstore?
...vents and had relied on them being reset when the app is installed. All my testing on the iPhone device (and Apples testing) tested the app as a new install. Without any documentation or way to test as an update I was unable to repeat the update crash all our customers are now experiencing. To sum u...
Correct way to detach from a container without stopping it
In Docker 1.1.2 (latest), what's the correct way to detach from a container without stopping it?
10 Answers
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Multiple variables in a 'with' statement?
...
class test2: x=1; t2=test2() with open('f2.txt') as t2.x: for l1 in t2.x.readlines(): print(l1); # Charlie Parker # tested in python 3.6
– Ahmad Yoosofan
Aug 12 '17 at 8:33
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