Can't take the mean of a 2D matrix (Array indices must be positive integers or logical values.)

I have a 3D data set that I'm trying to take the mean and std along a single dimension and then average the mean or the std along the other two dimensions. Once I get the mean or the std along one dimension I have a 2d matrix. I can take the mean of the first matrix (means), but I can't with the second 2d matrix (STDs) The error I get is

Array indices must be positive integers or logical values.

This should be really simple.

%get rid of headers

data = data_set(6:2165,1:2048,1:16);

%permute data putting temporal frames first

data_frames_first = permute(data,[3,1,2]);

%average all the frames

frames_avg = mean(data_frames_first);

%permute frames back to last

frames_avg_and_last = permute(frames_avg,[2,3,1]);

%average all of our 2160 rows

frames_rows_avg = mean(frames_avg_and_last);

%finally average vertically along our 2048 columns

mean = mean(frames_rows_avg)

%take std of all frames element by element

frames_std = std(data_frames_first);

%permute frames back to last

frames_std_and_last = permute(frames_std,[2,3,1]);

%average all of our 2160 rows of stds

frames_stds_rows_avg = mean(frames_std_and_last);

This where I get the error

Error (line 29)

frames_stds_rows_avg = mean(frames_std_and_last);

Array indices must be positive integers or logical values.

Thanks.

Answer 1

[Rik]

You are using mean both as a function name and a variable name.

Also, if you read the doc for mean, you will notice you can explicitly set the dimension to be reduced. If I recall correctly the same is true for std.

[Mike Bakeman]

Thanks a bunch!

[Rik]

You're welcome. If my answer solved your problem, please consider marking it as accepted answer. If not, feel free to comment with your remaining issues.