how to create a .dat files

I have an .xls file, with 60 arrays of purely numeric values (no variable names or dates) that i would like to convert to a .dat file. I've tried importing the xls into Matlab and saving it as a .dat file. This creates a .dat file but i get the following error when i try to load it:

>> load xdata.dat
??? Error using ==> load
*Number of columns on line 1 of ASCII file* xdata.dat
*must be the same as previous lines.*

Answer 1

[Image Analyst]

Use xlsread() to get the raw data (the third output argument.) Then use fprintf() to write out a .dat file in text form, or fwrite() to write out as binary. Examples are in the help for those functions.

[Carey-anne]

Thank-you for your suggestion....the code I wrote is below. It breaks down at fprintf since it only writes one data point to the .dat file:

close all;

clear all;

%load excel file 65 arrays with 64 datapoints for each arra y_

[num, txt, raw] = xlsread ('xdata.xls');

%create .dat file

fid = fopen ('xdata.dat', 'w');

_% write to .dat file.... everything breaks down here _

fprintf (fid, '%e/n', num);

% when i check, xdata.dat only has one data point

load xdata.dat;

[Image Analyst]

Num is probably a cell array, especially if there are 60 separate tables of various sizes, so you can't write it out like that. You have to write out each cell one at a time (untested code follows).

for col = 1 : cols
  for row = 1 : rows
    if ~isnan(num{row, col})
      fprintf(fid, '%f, ', num{row, col});
    end
  end
  fprintf(fid, '\n');
end

Please read the FAQ for a better understanding of cell arrays.

By the way you have to use a backslash with \n, not a forward slash.

[Carey-anne]

Thanks much for the clues, I discovered an easier code:

close all;

clear all;

%load excel file 65 arrays with 64 datapoints for each array

[num, txt, raw] = xlsread ('xdata.xls');

%write raw data to .dat file

dlmwrite('xdata.dat',raw, ' ')

% load .dat file

load xdata.dat

Answer 2

[Jerin Joseph Koshy]

space   = '    ';                           % placeholder between the columns

%%open the file
tfile    = fopen([filename '.dat'], 'w');    % overwrites existing file!

%%write the table top
for index = 1 : 2 : length(varargin)
    fprintf(tfile, char(varargin(index)));
    fprintf(tfile, space);
end

%%write the data
for index1 = 1 : length(varargin{2})

    fprintf(tfile, '\r\n');                    % newline
    for index2 = 2 : 2 : length(varargin)
        % values from data-vectors
        fprintf(tfile, '%12.9f', varargin{index2}(index1));
        fprintf(tfile, space);
    end
  end

%%close the file
fclose(tfile);

tfile value is showing -1 and getting error as

Error using fprintf
Invalid file identifier. Use fopen to generate a valid file identifier.

Error in CreateTexDat (line 28)
    fprintf(tfile, char(varargin(index)));

any solution??????

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
fid = fopen ('xdata.dat', 'w');
>> fclose(fid)
Error using fclose
Invalid file identifier. Use fopen to generate a valid file identifier.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

[Image Analyst]

Jerin, what is this about? Is it your "Answer" to Carey-anne's question? It looks like there is an error, so what is she supposed to do with this answer?

Are you sure you posted this on the right/intended page? Do you have a question?

[Walter Roberson]

You do not have write access to the directory you are cd'd to.