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Why use the params keyword?
...
One danger with params Keyword is, if after Calls to the Method have been coded,
someone accidentally / intentionally removes one/more required Parameters from the Method Signature,
and
one/more required Parameters immed...
What's the difference between belongs_to and has_one?
What is the difference between a belongs_to and a has_one ?
5 Answers
5
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How to delete items from a dictionary while iterating over it?
...ot modify a dictionary while iterating over it:
>>> mydict = {'one': 1, 'two': 2, 'three': 3, 'four': 4}
>>> for k, v in mydict.iteritems():
... if k == 'two':
... del mydict[k]
...
------------------------------------------------------------
Traceback (most recent cal...
adding multiple entries to a HashMap at once in one statement
I need to initialize a constant HashMap and would like to do it in one line statement. Avoiding sth like this:
9 Answers
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Can C++ code be valid in both C++03 and C++11 but do different things?
...n the appendix C of the standard. Even though there are many more negative ones than positive, each one of them is much less likely to occur.
String literals
#define u8 "abc"
const char* s = u8"def"; // Previously "abcdef", now "def"
and
#define _x "there"
"hello "_x // Previously "hello there", no...
Combined area of overlapping circles
...plementation details to handle all the special cases ( circle inside other one, no intersection, holes , one point contact ... )
– fa.
Nov 3 '09 at 16:03
1
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Implementing Comments and Likes in database
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The most extensible solution is to have just one "base" table (connected to "likes", tags and comments), and "inherit" all other tables from it. Adding a new kind of entity involves just adding a new "inherited" table - it then automatically plugs into the whole like/ta...
Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
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This creates four count columns, but how to get only one? (The question asks for "an additional column" and that's what I would like too.)
– Jaan
Jul 22 '15 at 6:58
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How to calculate moving average using NumPy?
..., which may be is faster than FFT based methods:
EDIT Corrected an off-by-one wrong indexing spotted by Bean in the code. EDIT
def moving_average(a, n=3) :
ret = np.cumsum(a, dtype=float)
ret[n:] = ret[n:] - ret[:-n]
return ret[n - 1:] / n
>>> a = np.arange(20)
>>> m...
What does principal end of an association means in 1:1 relationship in Entity framework
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In one-to-one relation one end must be principal and second end must be dependent. Principal end is the one which will be inserted first and which can exist without the dependent one. Dependent end is the one which must be inser...