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Default value for field in Django model
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Set editable to False and default to your default value.
http://docs.djangoproject.com/en/stable/ref/models/fields/#editable
b = models.CharField(max_length=7, default='0000000', editable=False)
Also, your id field is unnecessary. Django will...
Update a local branch with the changes from a tracked remote branch
...nch
(see:
"How do you make an existing git branch track a remote branch?" and
"Git: Why do I need to do --set-upstream-to all the time?"
)
git branch -f --track my_local_branch origin/my_remote_branch
# OR (if my_local_branch is currently checked out):
$ git branch --set-upstream-to my_local_bran...
Saving grid.arrange() plot to file
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grid.arrange draws directly on a device. arrangeGrob, on the other hand, doesn't draw anything but returns a grob g, that you can pass to ggsave(file="whatever.pdf", g).
The reason it works differently than with ggplot objects, where by default the last plot is being saved if not specified, ...
Private module methods in Ruby
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I think the best way (and mostly how existing libs are written) to do this is by creating a class within the module that deals with all the logic, and the module just provides a convenient method, e.g.
module GTranslate
class Translator
def...
How to extract text from a string using sed?
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That's why, isn't it? Replace whatever comes before and after the match with norhing, then print the whole line.
– tripleee
Jul 19 '12 at 21:01
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Remove elements from collection while iterating
...201-63361-3")));
books.add(new Book(new ISBN("0-201-63361-4")));
Collect and Remove
The first technique consists in collecting all the objects that we want to delete (e.g. using an enhanced for loop) and after we finish iterating, we remove all found objects.
ISBN isbn = new ISBN("0-201-63361-2"...
Validate uniqueness of multiple columns
Is there a rails-way way to validate that an actual record is unique and not just a column? For example, a friendship model / table should not be able to have multiple identical records like:
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css overflow - only 1 line of text
...d ... if there are more character to show because when length of line long and it goes out of written div.
– Moshii
Sep 29 '16 at 13:18
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Android emulator doesn't take keyboard input - SDK tools rev 20
I've upgraded the SDK tools to revision 20 (from 18) and since the upgrade, the emulator doesn't seem to accept input from laptop's keyboard. But only using the emulator's own 'soft' keyboard (that appears when an input field is focused).
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How to call Android contacts list?
I'm making an Android app, and need to call the phone's contact list. I need to call the contacts list function, pick a contact, then return to my app with the contact's name. Here's the code I got on the internet, but it doesnt work.
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