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Extract elements of list at odd positions
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Solution
Yes, you can:
l = L[1::2]
And this is all. 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...
How to 'bulk update' with Django?
...e to use:
ModelClass.objects.filter(name='bar').update(name="foo")
You can also use F objects to do things like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelCla...
Understanding what 'type' keyword does in Scala
I am new to Scala and I could not really find a lot about the type keyword. I am trying to understand what the following expression may mean:
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Scala actors: receive vs react
...come interested in functional languages. Recently I've started looking at Scala, which seems like a very nice language.
5 A...
Overlaying histograms with ggplot2 in R
...are visible through each other. So you probably want to use three separate calls to geom_histogram, where each one gets it's own data frame and fill:
ggplot(histogram, aes(f0)) +
geom_histogram(data = lowf0, fill = "red", alpha = 0.2) +
geom_histogram(data = mediumf0, fill = "blue", alpha...
PHP shell_exec() vs exec()
...ream as a string. exec returns the last line of the output by default, but can provide all output as an array specifed as the second parameter.
See
http://php.net/manual/en/function.shell-exec.php
http://php.net/manual/en/function.exec.php
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How Do I Fetch All Old Items on an RSS Feed?
I've been experimenting with writing my own RSS reader. I can handle the "parse XML" bit. The thing I'm getting stuck on is "How do I fetch older posts?"
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Emulating a do-while loop in Bash
...ly exits with 0 (and false with 1) the latter does absolutely nothing. You can check with which true.
– Fleshgrinder
Dec 2 '19 at 7:01
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Rebasing a branch including all its children
...h mass automated rebasing.
So here it is. Use it by saving it into a file called git-auto-rebase in your PATH. It's probably also a good idea to use the dry run (-n) option before you try it for real. It may be a little more detail than you really want, but it will show you what it's going to try t...
Python naming conventions for modules
I have a module whose purpose is to define a class called "nib". (and a few related classes too.) How should I call the module itself? "nib"? "nibmodule"? Anything else?
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