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How to define two fields “unique” as couple
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There is a simple solution for you called unique_together which does exactly what you want.
For example:
class MyModel(models.Model):
field1 = models.CharField(max_length=50)
field2 = models.CharField(max_length=50)
class Meta:
unique_together = ('field1', 'fi...
Android studio, gradle and NDK
...his out for two days until I saw your post and this solved my problem. I really think NDK build is better separately built by Android.mk command line makefile only, not by gradle script since C/C++ has been built by Makefile for more than 40 years!
– tonga
Jan ...
How to implement a tree data-structure in Java? [closed]
...object. It is fairly easy to implement simple trees to do what you need.
All you need to add are methods for add to, removing from, traversing, and constructors. The Node is the basic building block of the Tree.
share
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Is there a numpy builtin to reject outliers from a list
...ng like the following? That is, take a list d and return a list filtered_d with any outlying elements removed based on some assumed distribution of the points in d .
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Remove refs/original/heads/master from git repo after filter-branch --tree-filter?
... as a backup, in case you mess up your filter-branch. Believe me, it's a really good idea.
Once you've inspected the results, and you're very confident that you have what you want, you can remove the backed up ref:
git update-ref -d refs/original/refs/heads/master
or if you did this to many refs...
Inject service in app.config
...e into app.config, so that data can be retrieved before the controller is called. I tried it like this:
10 Answers
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Why should I care about lightweight vs. annotated tags?
...ity for the paranoid. Most of us aren't ever going to use it, but if you really want to verify everything before you put that software on your computer, you might want it.
Edit:
As for what to write in a tag annotation, you're right - there's not always much useful to say. For a version number tag...
How Drupal works? [closed]
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Drupal can be confusing on this front, partially because it has a relatively deep function stack. Although it's procedural PHP it's purely event/listener driven in its architecture, and there's no simple "flow" in the main PHP script for you to look though. I recently ...
Rails 4 - passing variable to partial
...buyer } %>
<%= render "account", account: @buyer %>
# @account.to_partial_path returns 'accounts/account', so it can be used to replace:
# <%= render partial: "accounts/account", locals: { account: @account} %>
<%= render @account %>
# @posts is an array of Post instances, so ...
How to sort a Ruby Hash by number value?
...ea.com" => 745, "siteb.com" => 9, "sitec.com" => 10 }
metrics.sort_by {|_key, value| value}
# ==> [["siteb.com", 9], ["sitec.com", 10], ["sitea.com", 745]]
If you need a hash as a result, you can use to_h (in Ruby 2.0+)
metrics.sort_by {|_key, value| value}.to_h
# ==> {"siteb.c...