Date: Sep 30, 2013 6:43 PM
Author: Derek Goring
Subject: Re: txt files, read and write

On Tuesday, October 1, 2013 8:56:06 AM UTC+13, Andreas  wrote:
> Hello, i have the following problem.
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> I have a cfd. file that i can read and edit it via text editor such as notepad. What i want, is from that file to change specific numbers in it. I already used a variety of the printf, textscan and such commands but the problem is that for some reason it changes the structure of the file.
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> The .cfd file is the following:
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> http://speedy.sh/u4JSp/Demo-CFD0-hallway.cfd
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> I want to change a number without ruin the structure of the file because then i use that file in a program. If i change the structure, the program will be unable to read it. What i mean by changing the structure, you will see by yourselves if you run the standard textscan and fprintf commands.
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> Thanks in advance, i am out of ideas here!!!


One way of retaining the structure of your file is to read it in holus bolus, then write it out the same way:
fid=fopen('myfile.txt','rt');
a=fscanf(fid,'%c'); % Now a is a long string containing everything, including CR LF tabs etc etc
fclose(fid);
% Make the changes in a
a=strrep(a,'OldNumber','NewNumber');
etc
% Write out the new version
fid=fopen('myfile_new.txt','wt');
fprintf(fid,'%c',a);
fclose(fid);