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How to toggle a value in Python
...gt; print "%.2f usec/pass" % (1000000 * t3.timeit(number=100000)/100000)
9.84 usec/pass
>>> stmt4="""
x=0
for i in xrange(0,100):
x=x-1
"""
>>> t4=timeit.Timer(stmt=stmt4)
>>> print "%.2f usec/pass" % (1000000 * t4.timeit(number=100000)/100000)
6.32 usec/pass
...
Is there a simple, elegant way to define singletons? [duplicate]
...StaaleStaale
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12
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How do I space out the child elements of a StackPanel?
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84
Another nice approach can be seen here:
http://blogs.microsoft.co.il/blogs/eladkatz/archive/201...
How can I get a precise time, for example in milliseconds in Objective-C?
...e is a weird conversion - last line of the first example is "return * (uint64_t *) &elapsedNano;" why not just "return (uint64_t)elapsedNano" ?
– Tyler
Dec 29 '10 at 23:00
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Usage of protocols as array types and function parameters in swift
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DarkDustDarkDust
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Python Pandas: Get index of rows which column matches certain value
... index,
In [56]: idx = df.index[df['BoolCol']]
In [57]: idx
Out[57]: Int64Index([10, 40, 50], dtype='int64')
then you can select the rows using loc instead of iloc:
In [58]: df.loc[idx]
Out[58]:
BoolCol
10 True
40 True
50 True
[3 rows x 1 columns]
Note that loc can also accep...
Can you build dynamic libraries for iOS and load them at runtime?
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DarkDustDarkDust
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Why is “using namespace std;” considered bad practice?
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96
@TomA: The problem with #define is that it doesn't restrict itself to namespaces, but tramples over the whole code base. A namespace alias ...
Append value to empty vector in R?
...<-append(a,pi)
}
}
)
# user system elapsed
# 11.06 5.72 16.84
These are very inefficient because R copies the vector every time it appends.
The most efficient way to append is to use index. Note that this time I let it iterate 1e7 times, but it's still much faster than c.
a=nume...
What is the use of “assert” in Python?
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96
Nit: assert is a statement and not a function. And unlike print, in Python 3 it's still a statement.
– Bob Stein
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