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Can someone explain collection_select to me in clear, simple terms?
...order(..) or something like that.
# In your example it is:
Author.all,
# then you should specify methods for generating options
:id, # this is name of method that will be called for every row, result will be set as key
:name_with_initial, # this is name of method that will be ...
Path of assets in CSS files in Symfony 2
...ge in /web/bundles/mynicebundle/images/devil.png
I have made a test with ALL possible (sane) combinations of the following:
@notation, relative notation
Parse with cssrewrite, without it
CSS image background vs direct <img> tag src= to the very same image than CSS
CSS parsed with assetic a...
How to sparsely checkout only one single file from a git repository?
...
Originally, I mentioned in 2012 git archive (see Jared Forsyth's answer and Robert Knight's answer), since git1.7.9.5 (March 2012), Paul Brannan's answer:
git archive --format=tar --remote=origin HEAD:path/to/directory -- filename...
Add up a column of numbers at the Unix shell
... . . .| x=$(echo <(cat)); echo $((0+${x// /+}+0)) if you want all bash all the time:
– qneill
Apr 3 '15 at 23:31
...
How to uncompress a tar.gz in another directory
...specific directory, you can simply cd into your target directory prior to calling tar; then you will have to give a complete path to your archive, of course. You can do this in a scoping subshell to avoid influencing the surrounding script:
mkdir foo
(cd foo; tar -xzf ../bar.tar.gz) # instead of ...
How can I quickly sum all numbers in a file?
...
For a Perl one-liner, it's basically the same thing as the awk solution in Ayman Hourieh's answer:
% perl -nle '$sum += $_ } END { print $sum'
If you're curious what Perl one-liners do, you can deparse them:
% perl -MO=Deparse -nle '$sum += $_ } END ...
How to create a density plot in matplotlib?
...with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the function covariance_factor of the gaussian_kde class. First, here is what you get without changing that function:
However, if I use the following code:
import...
What is the most robust way to force a UIView to redraw?
...ouble with that, you're likely running into one of these issues:
You're calling it before you actually have the data, or your -drawRect: is over-caching something.
You're expecting the view to draw at the moment you call this method. There is intentionally no way to demand "draw right now this ver...
Define make variable at rule execution time
...r are evaluated. In order to create the directory only when out.tar is actually fired, you need to move the directory creation down into the steps:
out.tar :
$(eval TMP := $(shell mktemp -d))
@echo hi $(TMP)/hi.txt
tar -C $(TMP) cf $@ .
rm -rf $(TMP)
The eval function evaluates a...
Standard way to embed version into python package?
...is also used in lots of 3rd-party modules, so it's the quasi-standard.
Usually, __version__ is a string, but sometimes it's also a float or tuple.
Edit: as mentioned by S.Lott (Thank you!), PEP 8 says it explicitly:
Module Level Dunder Names
Module level "dunders" (i.e. names with two lea...