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Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
List of lists changes reflected across sublists unexpectedly
...
When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...
Align contents inside a div
...d to make sure Standards Mode is on by using a suitable DOCTYPE.
If you really need to support IE5/Quirks Mode, which these days you shouldn't really, it is possible to combine the two different approaches to centering:
<div style="text-align: center">
<div style="width: 50%; margin: ...
Allowed memory size of 33554432 bytes exhausted (tried to allocate 43148176 bytes) in php
...gram in PHP in a way that consumes memory faster than you realise. Copying strings, arrays and objects instead of using references will do it, though PHP 5 is supposed to do this more automatically than in PHP 4. But dealing with your data set in entirety over several steps is also wasteful compared...
VIM Replace word with contents of paste buffer?
... the one that'd get overwritten by the change command.)
Registers are generally specified by typing " then the name (single character) of the register, like "ay then "ap to yank into register a, then put the contents of register a. Same goes for a change command. In this case, if you don't want the ...
Importing variables from another file?
...
from file1 import *
will import all objects and methods in file1
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Generate a heatmap in MatPlotLib using a scatter data set
...50 heatmap. If you want, say, 512x384, you can put bins=(512, 384) in the call to histogram2d.
Example:
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How to save an HTML5 Canvas as an image on a server?
I'm working on a generative art project where I would like to allow users to save the resulting images from an algorithm. The general idea is:
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`from … import` vs `import .` [duplicate]
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I just tried import urllib.request and it doesn't work at all (python 2.6.5 Ubuntu).
– tkone
Feb 24 '12 at 23:33
6
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Is there a way to make npm install (the command) to work behind proxy?
...roxy variable in a .npmrc file but it does not work. Trying to avoid manually downloading all require packages and installing.
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