How to find the time of the max peak in a signal?

I have a signal data (x) which is 2s long. There is a peack on the signal that I can find with the findpeaks(x) function.

I am wondering how to find the conrresponding time?

Thanks in advance,

Answer 1

[Star Strider]

The easiest way is to have findpeaks return the indices in the second output —

t = ...;                                                                %  Time Vector
s = ...;                                                                % Signal Vector
[pks,locs] = findpeaks(y);
peak_time = t(locs)

.

[Jan Ali]

Thanks for the answer. However, how can I get the max peak and corresponding time in a matrix?

I run the : [s,f,t] = stft(x,fs); where s is 61x1533 complex double

then:

[pks,locs] = findpeaks(s);

Error using findpeaks

Expected Y to be real.

Error in findpeaks>parse_inputs (line 199)

validateattributes(Yin,{'double','single'},{'nonempty','real','vector'},...

Error in findpeaks (line 136)

= parse_inputs(isInMATLAB,Yin,varargin{:});

>> [pks,locs] = findpeaks(abs(s));

Error using findpeaks

Expected Y to be a vector.

Error in findpeaks>parse_inputs (line 199)

validateattributes(Yin,{'double','single'},{'nonempty','real','vector'},...

Error in findpeaks (line 136)

= parse_inputs(isInMATLAB,Yin,varargin{:});

[Star Strider]

The findpeaks fucntion only operates on vectors, so it will be necessary to iterate through individual rows or columns (since I cannot determine that from what you wrote).

Also, it will be necessary to use the abs function to take calculate the magnitude of the complex elements that you input to findpeaks.

From the documentation for the input data:

Input data, specified as a vector. data must be real and must have at least three elements.

.