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'str' object does not support item assignment in Python
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105
In Python, strings are immutable, so you can't change their characters in-place.
You can, howe...
Python argparse: default value or specified value
...example=1)
% test.py --example 2
Namespace(example=2)
nargs='?' means 0-or-1 arguments
const=1 sets the default when there are 0 arguments
type=int converts the argument to int
If you want test.py to set example to 1 even if no --example is specified, then include default=1. That is, with
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Anonymous recursive PHP functions
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answered Mar 19 '10 at 20:03
Derek HDerek H
10.2k66 gold badges3232 silver badges3838 bronze badges
...
How do I check for null values in JavaScript?
... will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks against -1)) for funct...
How can I convert the “arguments” object to an array in JavaScript?
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730
+100
ES6 usin...
How can I extract a good quality JPEG image from a video file with ffmpeg?
...2).
To output a series of images:
ffmpeg -i input.mp4 -qscale:v 2 output_%03d.jpg
See the image muxer documentation for more options involving image outputs.
To output a single image at ~60 seconds duration:
ffmpeg -ss 60 -i input.mp4 -qscale:v 4 -frames:v 1 output.jpg
This will work with any vid...
How to position a div in the middle of the screen when the page is bigger than the screen
...it at http://jsfiddle.net/XEUbc/1/
#mydiv {
position:fixed;
top: 50%;
left: 50%;
width:30em;
height:18em;
margin-top: -9em; /*set to a negative number 1/2 of your height*/
margin-left: -15em; /*set to a negative number 1/2 of your width*/
border: 1px solid #ccc;
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Finding the index of elements based on a condition using python list comprehension
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answered Sep 1 '11 at 13:20
Mike GrahamMike Graham
60.5k1212 gold badges8484 silver badges119119 bronze badges
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How do I tell Matplotlib to create a second (new) plot, then later plot on the old one?
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edited Jun 10 '18 at 18:54
answered Aug 4 '11 at 1:40
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Generate random 5 characters string
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$rand = substr(md5(microtime()),rand(0,26),5);
Would be my best guess--Unless you're looking for special characters, too:
$seed = str_split('abcdefghijklmnopqrstuvwxyz'
.'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
.'0123456789!@#$%^&*()...