Hello,

I am trying to generate a frequency series using the FFT matlab algorithm. It is for a machine tool. Here is my code:

`spindle_speed = 960; % speed is in rpm`

N = 3; %Number of teeth in cutter

Fs = 1000; % Sampling frequency

T = 1/Fs; % Sampling period

L = (inv((spindle_speed/60))*1000)*50; % Length of signal 62.5 for one revolution of tool

delta_T = 62.5*20;t = (0+delta_T:(L-1))*T; % Time vector

f = Fs*(0:(L/2))/L; % frequency vector

The problem I am having is that when t starts from 0 then the frequency starts from 0 which is correct, but when t starts from 0+ delta_T, then frequency starts from 0, I dont want it to start from 0. I want the influence of delta_T on the frequency vector.

Does anybody know?

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