Erik Max Francis <[EMAIL PROTECTED]> writes:
> For a file hashing system (finding similar files, rather than identical ones),
> I need to be able to efficiently and quickly sum the ordinals of the bytes of
> a file and their squares. Because of the nature of the application, it's a
> requirement that I do it in Python, or only with standard library modules (if
> such facilities exist) that might assist.
>
> So far the fastest way I've found is using the `sum` builtin and generators::
>
> ordinalSum = sum(ord(x) for x in data)
> ordinalSumSquared = sum(ord(x)**2 for x in data)
>
> This is about twice as fast as an explicit loop, but since it's going to be
> processing massive amounts of data, the faster the better. Are there any
> tricks I'm not thinking of, or perhaps helper functions in other modules that
> I'm not thinking of?
Is this any faster?
ordSum, orsSumSq = (lambda c:c.real,c.imag)(sum(complex(ord(x),ord(x)<<1)
for x in data))
'as
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