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Multiple ModelAdmins/views for same model in Django admin
...l may be registered only once.
class PostAdmin(admin.ModelAdmin):
list_display = ('title', 'pubdate','user')
class MyPost(Post):
class Meta:
proxy = True
class MyPostAdmin(PostAdmin):
def get_queryset(self, request):
return self.model.objects.filter(user = request.user...
Iterate keys in a C++ map
...te on the keys instead of the pairs), then take a look at Boost's transform_iterator.
[Tip: when looking at Boost documentation for a new class, read the "examples" at the end first. You then have a sporting chance of figuring out what on earth the rest of it is talking about :-)]
...
Retrieve only the queried element in an object array in MongoDB collection
...atched shapes element:
db.test.find(
{"shapes.color": "red"},
{_id: 0, shapes: {$elemMatch: {color: "red"}}});
Returns:
{"shapes" : [{"shape": "circle", "color": "red"}]}
In 2.2 you can also do this using the $ projection operator, where the $ in a projection object field name repre...
What is the difference between typeof and instanceof and when should one be used vs. the other?
...ot work as expected and typeof works well ... developer.mozilla.org/En/Core_JavaScript_1.5_Reference/…
– farinspace
May 22 '09 at 19:37
55
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Python's many ways of string formatting — are the older ones (going to be) deprecated?
...0}".format(world, greeting='Hello')
and is extensible through the object.__format__() hook used to handle formatting of individual values.
Note that the old system had % and the Template class, where the latter allows you to create subclasses that add or alter its behaviour. The new-style system ...
Good examples of Not a Functor/Functor/Applicative/Monad?
...onoid;
instance Monoid Data.Void where
mempty = undefined
mappend _ _ = undefined
mconcat _ = undefined
Since _|_ is a legal value in Haskell, and in fact the only legal value of Data.Void, this meets the Monoid rules. I am unsure what unsafeCoerce has to do with it, because your pro...
pandas three-way joining multiple dataframes on columns
...ve some common column, like name in your example, I'd do the following:
df_final = reduce(lambda left,right: pd.merge(left,right,on='name'), dfs)
That way, your code should work with whatever number of dataframes you want to merge.
Edit August 1, 2016: For those using Python 3: reduce has been m...
Get local IP address
... edited Oct 17 '17 at 19:32
ivan_pozdeev
26.5k1010 gold badges7676 silver badges124124 bronze badges
answered Jul 23 '11 at 20:26
...
Python list of dictionaries search
... 3.6.4, W7x64.
from random import randint
from timeit import timeit
list_dicts = []
for _ in range(1000): # number of dicts in the list
dict_tmp = {}
for i in range(10): # number of keys for each dict
dict_tmp[f"key{i}"] = randint(0,50)
list_dicts.append( dict_tmp )
d...
How to get the directory of the currently running file?
In nodejs I use __dirname . What is the equivalent of this in Golang?
10 Answers
10
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