How to solve error "Index exceeds the number of array elements (1)."?

Hello everyone! I am trying to make a staircase threshold with auditory stimuli. My code is pretty simple: I have 5 sounds at frequencies immerse in noise, I randomise their presentation while decreasing or increasing the SNR depending on the response of the subject.

myPitches = [500, 1000, 1500, 2000, 2500];
condition_fs = [1 2 3 4 5];
howLong = .5;

presentedPitches = [];
for condition = 1:5 % five frequencies
    for trial = 1:20 % presentation for each frequency
        % Random presentation of sounds at different pitches
        RandPitches = randperm(5,1);
        pitch = myPitches(RandPitches(condition_fs)); 
        presentedPitches(condition_fs, trial) = pitch; % save pitches 
        pause(1.5)
        [beep] = MakeBeep(pitch, howLong, samplingRate);
    end 
end 

This is part of my code. The error occurs at line 5 "Index exceeds the number of array elements (1)". I can't work out what it even means and I can't solve it.

Can someone help me please?

Thanks a lot guys!

[Dhanashree Mohite]

As per my understanding, Line no. 5 should contain 'condition_fs' instead of 'condition'.

it should be:

for condition_fs = 1:5

Hope you have 'samplingRate' defined. Else it will give error as:

Undefined function or variable 'samplingRate'

[Luca Merolla]

Yes sorry, that was a little oversight that I corrected, and yes my samplingRate is defined. However, still the error occurs. I solved it this way:

pitch = myPitches(RandPitches);

and now seems to work fine.

Thank you for your help!

Answer 1

[KSSV]

myPitches = [500, 1000, 1500, 2000, 2500];
condition_fs = [1 2 3 4 5];
howLong = .5;
presentedPitches = [];
for condition = 1:5 % five frequencies
    for trial = 1:20 % presentation for each frequency
        % Random presentation of sounds at different pitches
        RandPitches = randperm(5,1);
        pitch = myPitches(condition_fs(RandPitches)); 
        presentedPitches(condition_fs, trial) = pitch; % save pitches 
        pause(1.5)
        [beep] = MakeBeep(pitch, howLong, samplingRate);
    end 
end 

[Luca Merolla]

Hi! I tried your suggestion but it doesn't work. Anyway, I seem to have solve it somehow, thank you!