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How can I round to whole numbers in JavaScript?
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edited Aug 6 '11 at 16:10
Jeremy
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answered Aug 6 ...
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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'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...
How to create json by JavaScript for loop?
...ID"); // this works too
var status = document.getElementsByName("status")[0];
var jsonArr = [];
for (var i = 0; i < status.options.length; i++) {
jsonArr.push({
id: status.options[i].text,
optionValue: status.options[i].value
});
}
</script>
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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...
Anonymous recursive PHP functions
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answered Mar 19 '10 at 20:03
Derek HDerek H
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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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Declare slice or make slice?
In Go, what is the difference between var s []int and s := make([]int, 0) ?
4 Answers
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How can I convert the “arguments” object to an array in JavaScript?
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730
+100
ES6 usin...
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...