Reading text files in Matlab
Using file io functions in Matlab is a bit of confusion due to the variety and the issue of vectorisation.
In the following snippet data is read back using:
fscanf : creates a vector row by row
textread (or its replacement textscan): creates matrix
importdata: creates matrix
load: creates matrix
I normally use 'textread' followed by my own vectorisation. textread has rich features such as skipping header, skipping columns ...etc.
clear all;
% create test file
data = [1 5 2 4 3 3 4 2 5 1];
filename = 'test_file.txt';
fid = fopen(filename, 'w');
fprintf(fid, '%d %d', data);
fclose(fid);
% (1) read file using fscanf
fid = fopen(filename, 'r');
y1 = fscanf(fid, '%d'); %interleaves columns
fclose(fid);
% (2) read file using textread (or textscan)
[ya,yb] = textread(filename,'%d%d');
y2 = [ya yb];
% (3) read file using importdata
y3 = importdata(filename);
% (4) read file using load
y4 = load(filename);
disp('-------------------------------------------------------------')
disp(' original vector data')
disp(data)
disp(' file content using fprintf')
disp(y2)
disp(' vector created by fscanf')
disp(y1)
