MATLAB: How to import multiple indexed .txt files using a loop

Question

MOTIVATION: I want to: a) create, b)save and c) import .txt-tables using an index i within a loop.

EXAMPLE:

To create and save .txt-tables I wrote (for example) the following command lines:

for i=1:5;
V{i}=i-10:i:i+10;
fid = fopen(sprintf('Q_%d.txt',i),'wt');
fprintf(fid, [repmat('%g\t', 1, size(V{i},2)-1) '%g\n'], V{i}.');
fclose(fid);
end;

PROBLEM:

Now I want to import the Q_index.txt files also using a loop, such as:

for j=1:5;
fid =fopen(sprintf('Q_%d.txt',j),'wt');
QIMPORTED{j}=textscan(fid,'%f','TreatAsEmpty','NA','EmptyValue',NaN);
fclose(fid);
end;

but I obtain only empty cells.

QUESTION: I wonder if someone knows how to import multiple text files such as TABLE_index.txt using at once

using a loop command.

Thank you in advance for your attention

Emerson

Answer 1

While reading the file, you are opening the file again in 'write mode'. This will empty the files.

Use 'r' instead of 'wt' when you are opening the file to for reading.

fid =fopen(sprintf('Q_%d.txt',j),'r');
QIMPORTED{j}=textscan(fid,'%f','TreatAsEmpty','NA','EmptyValue',NaN);