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Count number of records returned by group by
...rGroup,
COUNT(*) OVER () AS TotalRecords
from temptable
group by column_1, column_2, column_3, column_4
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How do you calculate the average of a set of circular data? [closed]
...e, A, from a set of angle measurements
a[i] 0<=i
sum_i_from_1_to_N sin(a[i])
a = arctangent ---------------------------
sum_i_from_1_to_N cos(a[i])
The method given by starblue is computationally equivalent, but his reasons are clearer and probably program...
How to hide TabPage from TabControl [duplicate]
... A frustration is that RemoveByKey then Add later upsets the order.
– Colonel Panic
Apr 7 '15 at 16:07
@...
How does deriving work in Haskell?
... Haskell Wiki:
In this example we use the following Haskell code
$(gen_render ''Body)
to produce the following instance:
instance TH_Render Body where
render (NormalB exp) = build 'normalB exp
render (GuardedB guards) = build 'guardedB guards
The function gen_render above is d...
What are the lesser known but useful data structures?
..., sorted linked lists, with efficiency comparable to a binary search tree (order log n average time for most operations).
They can be used as an alternative to balanced trees (using probalistic balancing rather than strict enforcement of balancing). They are easy to implement and faster than say,...
os.path.dirname(__file__) returns empty
...get the dirname of the absolute path, use
os.path.dirname(os.path.abspath(__file__))
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Accessing Object Memory Address
When you call the object.__repr__() method in Python you get something like this back:
9 Answers
...
Can a dictionary be passed to django models on create?
...our model is called MyModel:
# create instance of model
m = MyModel(**data_dict)
# don't forget to save to database!
m.save()
As for your second question, the dictionary has to be the final argument. Again, extra and extra2 should be fields in the model.
m2 =MyModel(extra='hello', extra2='world'...
How do I flag a method as deprecated in Objective-C 2.0?
...x is provided to mark methods as deprecated:
@interface SomeClass
-method __attribute__((deprecated));
@end
or:
#include <AvailabilityMacros.h>
@interface SomeClass
-method DEPRECATED_ATTRIBUTE; // or some other deployment-target-specific macro
@end
...
How can I create a copy of an object in Python?
... get a copy method (in 2, you'd use a slice to make a copy):
>>> a_list = list('abc')
>>> a_copy_of_a_list = a_list.copy()
>>> a_copy_of_a_list is a_list
False
>>> a_copy_of_a_list == a_list
True
Shallow Copies
Shallow copies are just copies of the outermost cont...