Help locating peaks

Hello all,

Here's an interesting problem...I have a vector full of results that are plotted against their respective FFT bins. When I go to find their peaks using [pks, locs] = findpeaks(x)...LOCS are obviously not the values of the actual bins, but instead are just indices of the bins.

How could I match the bin values to these indices instead, much appreciated!

JT

Answer 1

[Walter Roberson]

"values of the actual bins" is not well-defined here. Do you mean the frequency that corresponds to the bin number?

If so then as Wayne King posted earlier this year,

the DFT bins are spaced at intervals of Fs/N where N is the length of the DFT vector and Fs is the sampling frequency. The first bin is zero frequency.

Thus, ((sampling frequency) times (fft bin number minus one) divided by (length of fft result)) gives frequency associated with the bin number.