Reading unformatted text and converting to formatted

17 views (last 30 days)
Hi,
I have some files that contain raw text that is unformatted. These files have lots of lines and all of these lines are along the lines of
RFCH[0][0]:1, RFCH[0][1]:2, RFCH[0][2]:3,
etc. What I need to do is assign the value to the right of the colon to a corresponding matrix location, so the first 1 would go to [0,0] ([1,1] since Matlab probably wouldn't recognize [0,0]).
I know I can open the file using
fid=fopen(projectdir, 'r')
T=textscan(fid, '%s')
fclose(fid)
I am not really sure how go about this. Any help would be great.
  4 Comments

Sign in to comment.

Accepted Answer

Stephen23
Stephen23 on 24 Nov 2015
Edited: Stephen23 on 24 Nov 2015
You can read the whole file using fileread, identify the digits using regexp, convert the values to linear indices using sub2ind, and then simple linear indexing is all that is required to allocate the values from the file to the final matrix:
str = fileread('temp.txt');
% identify digits:
rgx = '[A-Z]+\[(\d+)\]\[(\d+)\]: *(\d+)';
C = regexp(str,rgx,'tokens');
% convert digits to numeric:
M = cellfun(@str2double,vertcat(C{:}));
M(:,1:2) = 1+M(:,1:2);
% convert to linear indices:
out = nan(max(M(:,1)),max(M(:,2)));
idx = sub2ind(size(out),M(:,1),M(:,2));
% allocate values:
out(idx) = M(:,3)
Because you did not provide any sample datafile I had to create my own, which contains only this string:
RFCH[0][0]:1, RFCH[0][1]:2, RFCH[0][2]:3, RFCH[2][2]:4
The code's output using my sample data file is this:
out =
1 2 3
NaN NaN NaN
NaN NaN 4
  4 Comments
Ibro Tutic
Ibro Tutic on 24 Nov 2015
Edited: Ibro Tutic on 24 Nov 2015
I am getting the same error as above, it seems the matrix C is an empty 0x0 matrix, which I assume is causing the error. The space after the colon was an error on my part, there is not supposed to be a space. I modified your script to take this into account and I am still receiving the same error.

Sign in to comment.

More Answers (1)

dpb
dpb on 24 Nov 2015
RFCH[0][0]:1, RFCH[0][1]:2, RFCH[0][2]:3,
fmt='RFCH[%d][%d]:%d';
fid=fopen('yorfile');
c=cell2mat(textscan(fid,fmt,'delimiter',',','collectoutput',1));
fid=fclose(fid);
X(c(:,1)+1,c(:,2)+1)=c(:,3);
  1 Comment
Stephen23
Stephen23 on 24 Nov 2015
Subscripted assignment dimension mismatch.
Error in temp (line 5)
X(c(:,1)+1,c(:,2)+1) = c(:,3);

Sign in to comment.

Categories

Find more on Data Type Conversion in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!