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Is it worth using Python's re.compile?
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I've had a lot of experience running a compiled regex 1000s of times versus compiling on-the-fly, and have not noticed any perceivable difference. Obviously, this is anecdotal, and certainly not a great argument against compiling, but I've found the difference to be negligible.
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Does the ternary operator exist in R?
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306
As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a ...
Days between two dates? [duplicate]
...er of days:
>>> from datetime import date
>>> a = date(2011,11,24)
>>> b = date(2011,11,17)
>>> a-b
datetime.timedelta(7)
>>> (a-b).days
7
And it works with datetimes too — I think it rounds down to the nearest day:
>>> from datetime import...
Should I return EXIT_SUCCESS or 0 from main()?
...eing conflicting answers: should the main routine of a C++ program return 0 or EXIT_SUCCESS ?
8 Answers
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Write bytes to file
I have a hexadecimal string (e.g 0CFE9E69271557822FE715A8B3E564BE ) and I want to write it to a file as bytes. For example,
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Principal component analysis in Python
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edited Sep 3 '10 at 11:40
nikow
19.6k66 gold badges4242 silver badges6969 bronze badges
answe...
Random float number generation
...need to employ a more advanced method.
This will generate a number from 0.0 to 1.0, inclusive.
float r = static_cast <float> (rand()) / static_cast <float> (RAND_MAX);
This will generate a number from 0.0 to some arbitrary float, X:
float r2 = static_cast <float> (rand()) / ...
In Typescript, How to check if a string is Numeric
... edited Feb 13 '18 at 14:19
k0pernikus
35.4k4040 gold badges154154 silver badges266266 bronze badges
answered May 3 '14 at 6:09
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Compare if BigDecimal is greater than zero
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It's as simple as:
if (value.compareTo(BigDecimal.ZERO) > 0)
The documentation for compareTo actually specifies that it will return -1, 0 or 1, but the more general Comparable<T>.compareTo method only guarantees less than zero, zero, or greater than zero for the appropriate ...
Why do enum permissions often have 0, 1, 2, 4 values?
Why are people always using enum values like 0, 1, 2, 4, 8 and not 0, 1, 2, 3, 4 ?
7 Answers
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