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Re: alternative to conv command
Posted:
Apr 29, 2011 10:18 PM


Hi,
thanks for your interest in my problem. You should try the complex case. In my computer, the real case took 8 secs and the complex case of the same size took 79 seconds. But when I use the fft method, the complex case took only about 4 seconds. this is huge savings!!
ImageAnalyst <imageanalyst@mailinator.com> wrote in message <0b2c972e170547f7a1382a26dcca2a91@n10g2000yqf.googlegroups.com>... > So you're filtering a signal that's "2048e3" (that's 2048000) long > with a kernel that's 2048 long? That's a big kernel. But it's still > fast. Look: > > clc; > data = rand(1,2048000); > tic > smoothedData = conv(data, ones(2049,1)/3); > toc > > Elapsed time is 1.541351 seconds. > > I made the kernel an odd number of elements (as is normally done) just > to make sure it's symmetric. > > > So did you try the Fourier method like I suggested?



