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std::vector performance regression when enabling C++11
I have found an interesting performance regression in a small C++ snippet, when I enable C++11:
1 Answer
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Using property() on classmethods
... (using the classmethod() function) for getting and setting what is essentially a static variable. I tried to use the property() function with these, but it results in an error. I was able to reproduce the error with the following in the interpreter:
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Python - Create a list with initial capacity
...bject %d" % ( i, )
result.append(message)
return result
def doAllocate( size=10000 ):
result=size*[None]
for i in range(size):
message= "some unique object %d" % ( i, )
result[i]= message
return result
Results. (evaluate each function 144 times and average ...
Is it valid to replace http:// with // in a ?
... we test our sites in Firefox, Safari, IE6, IE7 and Opera. These browsers all understand that URL format.
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Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
Why aren't python nested functions called closures?
...s in Python, and they match the definition of a closure. So why are they called nested functions instead of closures ?
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
27.4k66 gold badges6060 silver badges6060 bronze badges
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Abstract methods in Python [duplicate]
...what a metaclass is, don't worry about it. :-)
– kindall
Dec 8 '10 at 0:15
1
The linked tutorial ...
Remove all occurrences of a value from a list?
...on over the filter+lambda; the former is more readable in addition to generally more efficient.
– habnabit
Jul 21 '09 at 4:28
17
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What is the formal difference in Scala between braces and parentheses, and when should they be used?
...ut this, but I gave up in the end, as the rules are somewhat diffuse. Basically, you’ll have to get the hang of it.
Perhaps it is best to concentrate on where curly braces and parenthesis can be used interchangeably: when passing parameters to method calls. You may replace parenthesis with curly b...