Almost all cases, 1st, use FFT2 transfer to frequency field all , then to analysis like filter.
If I know only some frequecy are need,
Is it possible to calculate only several frequency not all frequencies with FFT ?
If OK, How to do？
for example, if ther are 512 data points, then will get 512 data points at frequency field, but I only need 0~50Hz,
How to tall FFT no need to calculated those dat more than 50Hz ?
Like sparse , but not source dat sparse, is the transfer tanget is sparse .Almost all cases, 1st, use FFT2 transfer to frequency field all , then to analysis like filter.
If I know only some frequecy are need,
Is it possible to calculate only several frequency not all frequencies with FFT ?
If OK, How to do？
for example, if ther are 512 data points, then will get 512 data points at frequency field, but I only need 0~50Hz,
How to tall FFT no need to calculated those dat more than 50Hz ?
Like sparse , but not source dat sparse, is the transfer tanget is sparse . Almost all cases, 1st, use FFT2 transfer to frequency field all , then to analysis like filter.
If I know only some frequecy are need,
Is it possible to calculate only several frequency not all frequencies with FFT ?
If OK, How to do？
for example, if ther are 512 data points, then will get 512 data points at frequency field, but I only need 0~50Hz,
How to tall FFT no need to calculated those dat more than 50Hz ?
Like sparse , but not source dat sparse, is the transfer tanget is sparse . fft, sparse MATLAB Answers — New Questions

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