Hi. I want to define repetitive vectors from notepad data using loop

I am using an analysis program and it gives me a data in form of steel#.out. I made a code to load this data like

steellayer=#;

for ii = 1:steellayer

    load(['Steel' num2str(ii) '.out'])

end

and from this code I have Steel1, Stee2, Steel3, .... Steel#.

Each data is a 1000x3 matrix and I just need second and third column from each matrix.

Second column is 'stress' and third column is 'strain' I want to have 'strain1', 'strain2','strain3'.....,'strain#' and 'stress1','stress2','stress3'...,'stress#' for each matrix

I can define each vector but it is not efficient since # varies by chases and I need to change it all the time.

Therefore, I want to make those vectors automatically no matter what # is.

I tried to make it using 'eval' function like this

for n=1:steellayer

eval(['Strain', int2str(steellayer),' = Steel',int2str(steellayer)'])

end

but I cannot pick a certain column and it just makes same matrix as Steel1.... Steel#.

I would really appreciate for any help.

Thanks.

[Jos (10584)]

Don't! Instead of using variables A1, A2, ... Ax, use a single variable, like a cell array A{k}, an array of structs A(k).data, or perhaps a regular arrays A(k,:), to store and process your data. This avoids the evil eval construction.

To generate column headers in a text file simply use fprintf as in

fprintf(fid,'Steel%02d',k)

[Stephen23]

Don't!

Load your data into one variable:

for k = 1:numel(files)
    S(k) = load(files{k});
end

Or put your data into one cell array or one numeric array... whatever suits your data best.

http://www.mathworks.com/help/matlab/matlab_prog/string-evaluation.html

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

Answer 1

[Jan]

Please read http://www.mathworks.com/matlabcentral/answers/196952#answer_174587 . Stephen has discussed the topic exhaustively.