How to change time interval value when using instfreq function in Matlab ?

When I want to use instfreq function to acquire average frequency versus time,

eg. [frequency, time]=instfreq(signal,fs);

here if my signal length is 2240 points, and my sample frequency fs is 16Hz, my time interval is always 2.125s, and the length is always 63.

I find that time interval is fixed. I try several format about this function, but I fail to change the time interval.

I wounder if any other methods could help me to acquire feasible time interval in this function?

Answer 1

[SaiDileep Kola]

You can customize the time interval using Frequency Resolution, to quote an example

To explain from your case

fs = 16;
t = (0:1/fs:140-1/fs)';
x = sin(2*pi*200*t) + randn(size(t))/4;   %this is the signal I have taken to explain
instfreq(x,t)  % gives default time interval
%instead you can do as below
[p,fd,td] = pspectrum(x,t,'spectrogram','FrequencyResolution',40); 
% the last argument is to customize the time interval
% you get the range of argument when you execute the command if it exceeds the range
[f1,t1]=instfreq(p,fd,td); 

[Yihan Ma]

Thanks,

it worked.