how to read a matrix from a text file in matlab

Question

I have a text file which has 500 columns and 500 rows, of numerical(integer) values . Every element in the row is separated by a tab. I want to read this file as a matrix in matlab. Example(my text file is like this):

 1 2 2 1 1 2 
 0 0 0 1 2 0
 1 2 2 1 1 2 
 0 0 0 1 2 0

And after reading this text file as a matrix (a[]) in matlab I want to do transpose. Help me.

Answer 1

Have you tired load with -ascii option?
For example

 a = load('myfile.txt', '-ascii'); % read the data
 a = a.'; %' transpose

Answer 2

You could simply do:

yourVariable = importdata('yourFile.txt')';
%Loads data from file, transposes it and stores it into 'yourVariable'.

Answer 3

% Pre-allocate matrix
Nrow=500; Ncol=500;
a = zeros(Nrow,Ncol);
% Read file
fid = fopen('yourfile.txt','r');
for i:1:Nrow
   a(i,:) = cell2mat(textscan(fid,repmat('%d ',Ncol));
end
fclose(fid); 
% Trasnspose matrix
a_trans = a.';

Answer 4

You can use importdata. Something like:

filename = 'myfile01.txt';
delimiterIn = '\t';
headerlinesIn = 1;
A = importdata(filename,delimiterIn,headerlinesIn);
A_trans = A';

You can skip headerlines if your file does not have any haeder.. (It is the number of lines before the actual data starts)

Taken from Matlab documentation, improtdata