How can I print variables within a function?

Good day to all,

1st time posting here so I apologize for any errors. I am currently working on a script which uses the mat2tiles script. Essentially when the data is analyzed a variable called number_of_segments which can vary based on the size of data is created. This value is created by my script and can range from 1 to 1000. From this point I use the following code (which works)

    % code
for i = 1:number_of_segments;
    s=['Seg' int2str(i) '= mean(bandpower(data3{i,1},sampling_rate,[low_delta,high_delta;low_theta,high_theta;low_alpha1,high_alpha1;low_alpha2,high_alpha2;low_beta1,high_beta1;low_beta2,high_beta2,low_beta3,high_beta3;low_gamma,high_gamma],1,1))'];
    eval(s);
end

This creates several variables which are named Seg1 to SegX where X is defined by the variable number_of_segments. Each Seg1 to SegX file is a 1x152 double array. My goal is to automatically concatenate these Seg1 to SegX arrays into one larger array which I have called TotalSegments.

I can do this by hand in the Command Window. For example if I know that number_of_segments = 5 then in order to get my desired result the code would be (this code works)

    % code
TotalSegments=vertcat(Seg1,Seg2,Seg3,Seg4,Seg5);
  end

The problem is that the variable number_of_segments changes for each file. I would like the script to output my result. My issue is that I do not know how to print this in MatLab. Here is what I have attempted (This code does NOT work)

    % code
for i = 1:number_of_segments;
    s=[int2str(i) 'TotalSegments= vertcat(Seg(i));'];
    eval(s);
end

Does anyone know how this might be achieved? I appreciate any input. Thank You

Currently using MatLab R2014a

Answer 1

[Michael Haderlein]

Dear Andrew,

you shouldn't name your variables this way. Better use the index as what it is: an index.

for i = 1:number_of_segments;
    Seg(:,i) = mean(bandpower(...))';
end

That results in an 152-x-number_of_segments double array.

Concenating is then a simple job:

C_Seg=Seg(:)'

Best regards,

Michael

[Andrew]

Good day Michael,

Thank you very much for your response, you clearly have a great grasp of MatLab coding. I believe this is what you wanted me to try (I've removed a few variables so it so it takes less space)

    % code
for i = 1:number_of_segments;
    Seg(:,i)= mean(bandpower(data3{i,1},sampling_rate,[low_delta,high_delta;low_theta,high_theta],1,1))];
end

However I am getting a "Unbalanced or unexpected parenthesis or bracket" error. I have tried to input the code several different ways with no success.

Method #2

 % code
for i = 1:number_of_segments;
    Seg(:,i)= 'mean(bandpower(data3{i,1},sampling_rate,[low_delta,high_delta;low_theta,high_theta],1,1))]';
end

If I use Method #2, the script will run however the Seg1 to SegX files are not created. I've also tried Method #3

Method #3

    % code
for i = 1:number_of_segments;
    'Seg'(:,i)= 'mean(bandpower(data3{i,1},sampling_rate,[low_delta,high_delta;low_theta,high_theta],1,1))]';
end

This method also gives me a "Unbalanced or unexpected parenthesis or bracket" error.

Any ideas? Thank you once again for your kind response.

Sincerely,

Andrew

[Patrik Ek]

Hi, you must fix the paranthesis and brackets at the end. Right now it looks something like (method #1) mean(...]; Obviously a typo, but these can be hard enough to find. Especially for the person that wrote the code :)

[Andrew]

Thank you very much to both of you for your help. The final code for those who may revisit this post is as follows

    % code
for i = 1:number_of_segments;
    Segment(:,i)= mean(bandpower(data3{i,1},sampling_rate,[low_delta,high_delta;low_theta,high_theta;low_alpha1,high_alpha1;low_alpha2,high_alpha2;low_beta1,high_beta1;low_beta2,high_beta2;low_beta3,high_beta3;low_gamma,high_gamma],1,1));
end

Thank you very much once again!