Re: How to increase the speed of this program?

HYRY wrote:
Peter Otten wrote:
HYRY wrote:

I want to join two mono wave file to a stereo wave file by only using
the default python module.
Here is my program, but it is much slower than the C version, so how
can I increase the speed?
I think the problem is at line #1, #2, #3.

oarray = array.array("h", [0]*(len(larray)+len(rarray))) #1

ITEMSIZE = 2
size = ITEMSIZE*(len(larray) + len(rarray))
oarray = array.array("h")
oarray.fromstring("\0" * size)

may be a bit faster.

Peter

Thank you very much, that is just what I want.

Even faster: oarray = larray + rarray

C:\Python25>python -m timeit -s"from array import array; N = 10**6" "a
=array('h'); a.fromstring('\0'*(2*N))"
100 loops, best of 3: 9.57 msec per loop

C:\Python25>python -m timeit -s"from array import array; N = 10**6; b =
array('h', [0])*(N/2); c = b[:]" "a = b + c"
100 loops, best of 3: 5.7 msec per loop

-- Leo

.

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