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dpb
Posts:
9,716
Registered:
6/7/07


Re: Need help in doing fft for a large matrix
Posted:
Feb 7, 2013 2:02 PM


On 2/7/2013 7:34 AM, Gupta wrote: > Hello...i ma trying to do abs(fft(y))) where y a large matriy of size > 1x8388608. when i am running the code, at this line the program was > getting terminated without running remaining commands. was the problem > is with size of the matrix or memory of matlab or fft funtion. when i do > this operation for a mtrix of size 1x4194304 it was working perfect.
Well, on its own
x=rand(1x8388608); f=abs(x);
was no problem here w/ a machine w/ only 1GB actual memory on either R121 or R2012b so by itself size wouldn't appear to be the issuehow much other memory is being used at the time?
The combination of x and f above is only 128 MB; it almost certainly requires another complex of the same size as working space plus some other additional...
What error is givenis it memory or something else?
Post any error messages and the result of
whos
and/or
memory




