How to plot a stacked histogram from multi text files

I want to make a stacked histogram from multi text files, from TS2004.07.01.0000.txt to TS2004.07.31.2100.txt. But following program has a error:

for i = 1:31
    if i<10
       daystr = ['0', num2str(i)];
    else
       daystr = num2str(i);
    end
    for k = 0:7
        j = 3*k;
       if j<10
          hour = ['0', num2str(j)];
       else
          hour = num2str(j);
       end
       filename = ['TS2004.07.',daystr,'.',hour,'00.txt'];
       [y, b] = hist(filename);
       bar(b,y,'stacked');
    end 
end
error:

>> hist
Attempt to execute SCRIPT hist as a function:
/Users/naoki/Documents/MATLAB/Add-Ons/TS2004.07/hist.m
Error in hist (line 15)
       [y, b] = hist(filename); 
please give me any advice!

[michio]

Related Q: http://jp.mathworks.com/matlabcentral/answers/302666-

Answer 1

[michio]

In the script above you call hist function

[y, b] = hist(filename);

which causes an error, whose message indicates that hist.m (/Users/naoki/Documents/MATLAB/Add-Ons/TS2004.07/hist.m) is a script not a function. It seems it's not hist.m that Mathworks provides.

Did you intend to call hist.m as a function? If so, could you double-check if hist.m is a function? Is this a function that you created?

[michio]

Once the above issue is resolved, bar function with 'stacked' option is a right direction to go if you want to make a stacked histogram.

But still I believe it should be called outside of for-loop as I mentioned in the related entry (<http://jp.mathworks.com/matlabcentral/answers/302666->)

y should be a 31 x nbin array, where nbin is the number of bins, in your case.