假设要读取的文本文件为test.txt，文件内容分别如下：

1 2 3
4 5 6
7 8 9

A 1 2 3
B 4 5 6
C 7 8 9

读取纯数据文件

>> I = load('test.txt')

I =

     1     2     3
     4     5     6
     7     8     9

读取文本和数据混合文件

方法一：importdata

>> I = importdata('test.txt')

I = 

          data: [3x3 double]
      textdata: {3x1 cell}
    rowheaders: {3x1 cell}

>> I.data

ans =

     1     2     3
     4     5     6
     7     8     9

>> I.textdata

ans = 

    'A'
    'B'
    'C'

>> I.rowheaders

ans = 

    'A'
    'B'
    'C'

方法二：textscan

>>  fid = fopen('test.txt');
>> C = textscan(fid,'%s %d %d %d');
>> C{1}

ans = 

    'A'
    'B'
    'C'

>> C{2}

ans =

           1
           4
           7

>> C{3}

ans =

           2
           5
           8

>> C{4}

ans =

           3
           6
           9

输出矩阵到文本文件

function mat2txt(M)
% 输出矩阵到txt文件

[m,n] = size(M);
fid = fopen('D:\matlab\DIP\qxy\data.txt','wt');
for i = 1 : m
    for j = 1 : n
        if j == n
            fprintf(fid,'%4.3f\n',M(i,j));
        else
            fprintf(fid,'%4.3f\t',M(i,j));
        end
    end
end
fclose(fid);

转载：http://blog.csdn.net/foreverling/article/details/44925097