smarter and faster way to read several files

Question

aneps 2016-5-2

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/282218-smarter-and-faster-way-to-read-several-files

回答： Walter Roberson 2016-5-2

I have several data files (.dat) on which I want to perform the following code:

NL=8;
Name = 'Output_1';
filename = [Name,'.dat'];
      if ~exist(filename, 'file')
          error('Your data file %s does not exist in this directory', filename);
      end
      [fid, message] = fopen(filename, 'rt');
      if fid < 0
          error('Opening the file %s failed because %s', filename, message);
      end
      Data = cell2mat( textscan(fid, '%f%f%f', 'Delimiter', '\t', 'TreatAsEmpty', ...
         'nil', 'EmptyValue', 0, 'CollectOutput', 1,'headerlines',NL) );
     fclose(fid);
m1=300;
m2=600;
index_1 = find(Data(:,1)==m1);
Data_1=Data(index_1,:);
Data_m1=[Data_1(:,1) Data_1(:,2)];
index_2 = find(Data(:,1)==m2);
Data_2=Data(index_2,:);
Data_m2=[Data_2(:,1) Data_2(:,2)];
nbins = min(Data_1(:,2)):1:max(Data_2(:,2));
[NX1 X]=hist(Data_1(:,2),nbins);
figure(1)
plot(X,NX1,'b')
hold on
[NX2 X]=hist(Data_2(:,2),nbins);
figure(1)
plot(X,NX2,'r')

Here I am reading the data from file with name Output_1 and find those indices corresponding to X= 300 and 600. Then plot the histogram of corresponding Y. How can I loop this to perform the same operation on several files named Output_1, Output_2....Output_n and then accumulate the plot with different colors or markers to identify the files?