How to read an ascii text file and extract the data in a matrix?

I have a ascii text file (B1N.SA) with 250 blocks of data which each block have 25 header line and then the data (as you can see below). I don't need the first 25 character and the last 5 character ( *). Could you please help me? I need just in each block to have such as a matrix 299*299.

[Sara]

Have you looked into textscan? the file or image is missing

Answer 1

[per isakson]

Try

    out = read_blocks_of_numerical_data( 'B1N.SA', 1000, ',' );

where

    function    out = read_blocks_of_numerical_data( filespec, block_size, delimiter )

        narginchk( 2, 3 )
        buffer  = fileread( filespec );

        if nargin == 2 
            del_xpr = '[ ]+';
            trl_xpr = '[ ]*';
        else
            del_xpr = ['([ ]*',delimiter,'[ ]*)'];
            trl_xpr = ['([ ]*',delimiter,'?[ ]*)'];
        end

        num_xpr = '([+-]?(\d+(\.\d*)?)|(\.\d+))';
        sen_xpr = '([EeDd](\+|-)\d{1,3})?'; % optional scientific E notation
        num_xpr = [ num_xpr, sen_xpr ];

        nl_xpr  = '((\r\n)|\n)';

        row_xpr = cat(2,'(^|',nl_xpr,')[ ]*(', num_xpr, del_xpr, ')*'   ...
                        , num_xpr, trl_xpr, '(?=',nl_xpr,'|$)'          ); 

        blk_xpr = ['(',row_xpr,')+'];

        blocks  = regexp( buffer, blk_xpr, 'match' );

        is_long = cellfun( @(str) length(str)>=block_size, blocks );

        blocks(not(is_long)) = [];

        out = cell( 1, length( blocks ) ); 
        for jj = 1 : length( blocks )
            out{jj} = str2num( blocks{jj} );        
        end
    end

[Baban]

Thanks for your reply It's gave just an cell 1*0. and why for block size 1000??

[per isakson]

block_size is a lower limit of the number of characters in a block of numerical data. I just made a guess.

Why don't you attach a sample file? It's difficult to help without knowing more about the file.