Is the 'findpeaks' function available only in 2014b ?

I am getting this error "Undefined function 'findpeaks' for input arguments of type 'double' " while using 'findpeaks' in Matlab 2014a

Answer 1

[Mischa Kim]

Harish, findpeaks is part of the Signal Processing Toolbox, which you might not have licensed/installed. To check if you do enter at the command prompt

 >> which findpeaks

which should return something like

 C:\Program Files\MATLAB\R2015a\toolbox\signal\signal\findpeaks.m

in case you have access to the toolbox.

[geotocho]

Mischa I am having this same issue. My code runs on 2015b. When I moved to a different machine with 2014a I receive the same error as OP. I have the Signal Processing Toolbox. I validated this using the command which findpeaks.

Answer 2

[geotocho]

I beleive the issue you have, or may have resolved by now, is caused by the findpeaks input arguments. findpeaks has changed since MATLAB2014a. Currently findpeaks accepts a vector of indicies as the second argument for which [~,locs] is identified by. The 2014a version does not handle this index array as the second function argument. 2014a is looking for a string such as 'Tolerance' for the second input. 2014a findpeaks will output locs which may not precisely be the locs you want if you search only a portion of your signal for peaks.

To work around this and output the peak locs identified by 2014a I modified my code below:

% Find Peak Change in Covariance - Evaluated 99% Probability

% 2014b or later Version

[~,peakIx]=findpeaks(qCovAvg(100:end),Ix(100:end),'MinPeakHeight',q99);

% 2014a or Earlier Version

[~,peakIx] = findpeaks(qCovAvg(100:end),'MinPeakHeight',q99);

dumIx = Ix(100:end);

peakIx = dumIx(peakIx);

% Hope you find this helpful