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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...
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...
Pandas percentage of total with groupby
...swer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1, 7)) * 2,
'sales': [np.random.randint(100000, 999999)
for _ in range(12...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
...
640
Difference between == and ===
The difference between the loosely == equal operator and the stri...
Is 0 a decimal literal or an octal literal?
...hat actually almost all integer literals in my code are octal, namely 0 .
3 Answers
...
Append value to empty vector in R?
...et.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time( for (i in 1:length(values)) vec...
How do I get an object's unqualified (short) class name?
...
jeremysawesome
6,15733 gold badges3030 silver badges3232 bronze badges
answered Nov 11 '13 at 15:09
lonesomedaylonesomeday
...
How to configure PostgreSQL to accept all incoming connections
...
Just use 0.0.0.0/0.
host all all 0.0.0.0/0 md5
Make sure the listen_addresses in postgresql.conf (or ALTER SYSTEM SET) allows incoming connections on all available IP interfaces.
listen_addres...
Python unittests in Jenkins?
...il("shouldn't happen")
def test_pass(self):
self.assertEqual(10, 7 + 3)
def test_fail(self):
self.assertEqual(11, 7 + 3)
JUnit with pytest
run the tests with:
py.test --junitxml results.xml tests.py
results.xml:
<?xml version="1.0" encoding="utf-8"?>
<testsu...
Specify pane percentage in tmuxinator project
...r use with select-layout. For example:
$ tmux list-windows
0: ksh [159x48]
layout: bb62,159x48,0,0{79x48,0,0,79x48,80,0}
$ tmux select-layout bb62,159x48,0,0{79x48,0,0,79x48,80,0}
tmux automatically adjusts the size of the layout for the current window
size. Not...