I am getting the following error in my code: "Undefined function or variable 'helperFre​quencyAnal​ysisPlot2'​." How do I correct this error?

function [domPks, domF, medF] = domFreqs(d, Fs, n, plots) %UNTITLED Summary of this function goes here % Detailed explanation goes here

% Input % d: data % Fs: sampling freq % n: number of dominant frequenies to return % plots: = 1 to display plots

    NFFT = length(d);              % Number of FFT points
    F = (0 : 1/NFFT : 1/2-1/NFFT)*Fs; % Frequency vector

    TEMP = fft(d,NFFT);
    TEMP(1) = 0; % remove the DC component for better visualization

    [pksTemp,~] = findpeaks(abs(TEMP(1:floor(NFFT/2))));

    % Sort frequency peaks
    pks = sort(pksTemp,1,'descend');

    for i = 1:n
        loc(i) = find(abs(TEMP(1:floor(NFFT/2))) == pks(i));
    end

    if plots == 1
        % Plot 1st and 2nd dominant peaks
        helperFrequencyAnalysisPlot2(F,abs(TEMP(1:floor(NFFT/2))),...
            'Frequency (cycles/s)','Magnitude',[],[],[0 5])
        hold on
        plot(F(loc),pks(1:n),'ro')
    end

    domPks = pks(1:n);
    domF = F(loc(1:n));
    medF = median(pks);

end

Answer 1

[Walter Roberson]

Chances are that you are trying to use an example code with a version of MATLAB earlier than what the example was designed for.

Which MATLAB version are you using?