DFT_time2freq

DFT_time2freq(t, val, freq, signal_type)

Full definition:

f_val = DFT_time2freq( t, val, freq, signal_type )

computes the DFT at the given frequencies

parameter:

• t : time vector

• val: data vector

• freq: DFT frequency vector

• signal_type: ‘pulse’ (default), ‘periodic’

return values:

• f_val: single-sided spectrum

example:

t=linspace(0,1,100);
t_val=0.9*sin(2*pi*3*t); % sine wave; amplitude 0.9; frequency 3 Hz
f=linspace(1,5,101);
f_val=DFT_time2freq( t, t_val, f, 'periodic' );
interp1(f,abs(f_val),3)
% ans = 0.8910
plot( t, t_val )
plot( f, abs(f_val) )