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Django admin: How to display a field that is marked as editable=False' in the model?
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+1. Especially if you don't plan to edit the field at all in Admin.
– Manoj Govindan
Oct 19 '10 at 16:05
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Difference between Django's annotate and aggregate methods?
...rage_price': 34.35}
Returns a dictionary containing the average price of all books in the queryset.
Annotation
>>> q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been...
How do I use FileSystemObject in VBA?
...set a reference to the VB script run-time library.
The relevant file is usually located at \Windows\System32\scrrun.dll
To reference this file, load the
Visual Basic Editor (ALT+F11)
Select Tools > References from the drop-down menu
A listbox of available references will be displayed
Tick the c...
Run a callback only if an attribute has changed in Rails
...tiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c6a08383b974ae6c96faac5b4a3c81
Here is a blog post on these cha...
Where does the “flatmap that s***” idiomatic expression in Scala come from?
...t you can replace a lot of tedious if/then/else code you would write with calls to flatMap (and other higher order functions).
This is especially true for Options (see http://tonymorris.github.io/blog/posts/scalaoption-cheat-sheet/)
But it applies to other monads as well (although I have to admit...
Linux command or script counting duplicated lines in a text file?
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Send it through sort (to put adjacent items together) then uniq -c to give counts, i.e.:
sort filename | uniq -c
and to get that list in sorted order (by frequency) you can
sort filename | uniq -c | sort -nr
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git + LaTeX workflow
...ve my work computer and my laptop, and I work on them both. I need to keep all the files synchronized between the two computers, and also would like to keep a revision history. I chose git as my DVCS, and I'm hosting my repository on my server. I'm also using Kile + Okular to do the editing. Kile do...
Class method differences in Python: bound, unbound and static
...n Python, there is a distinction between bound and unbound methods.
Basically, a call to a member function (like method_one), a bound function
a_test.method_one()
is translated to
Test.method_one(a_test)
i.e. a call to an unbound method. Because of that, a call to your version of method_two ...
where is gacutil.exe?
...amilyId=F26B1AA4-741A-433A-9BE5-FA919850BDBF&displaylang=en . This installation will have gacutil.exe included. But first check it here
C:\Program Files\Microsoft SDKs\Windows\v6.0A\bin
you might have it installed.
As @devi mentioned
If you decide to grab gacutil files from existing ins...
What is the maximum float in Python?
I think the maximum integer in python is available by calling sys.maxint .
3 Answers
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