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

13 次查看（过去 30 天）
Yihan Ma
Yihan Ma 2019-7-30
评论： Yihan Ma 2019-8-27
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?

请先登录，再回答此问题。

采纳的回答

SaiDileep Kola
SaiDileep Kola 2019-8-2
编辑：madhan ravi 2019-8-2
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);

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Surrogate Optimization 的更多信息

标签

产品


版本

R2018b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by