loading text file to matrix without delimiters
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I have a text file dataset with Y number of lines and each line has exactly 250 characters (including spaces).
I want to put each character (even if it is a space) into a matrix so I create a matrix with 250 columns and Y rows. We can replace the spaces with NaN.
I have been playing with textscan and few other functions but cannot seem to get it. Anyone have any ideas?
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Accepted Answer
Jos (10584)
on 2 Apr 2014
So each digit is a single value, and spaces are to be replaced with NaN …
M = char(textread('example.txt','%s','delimiter','')) - '0' ;
M(M==(' '-'0')) = NaN ; % replaces spaces with NaN's
% M is now a 4-b-250 numerical array
btw the second line of example.txt is 251 characters long
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More Answers (5)
Azzi Abdelmalek
on 2 Apr 2014
d=importdata('file.txt')
3 Comments
Azzi Abdelmalek
on 2 Apr 2014
This is not clear. Do you want to import numeric data or what? Post the four line of your file
Image Analyst
on 2 Apr 2014
When I saved your example it didn't have exactly 250 characters on every line. I had 251 in the second line for some reason and the last line had only 1 character. So I made the code a little more robust than you might need it, but extra robustness never hurts.
fid = fopen('example.txt');
tline = fgetl(fid);
lineCounter = 1;
charArray = tline;
fprintf('%d characters in line #%d: %s\n', length(tline), lineCounter, tline)
while ischar(tline)
tline = fgetl(fid);
if length(tline) < 3
continue;
end
fprintf('%d characters in line #%d: %s\n', length(tline), lineCounter, tline)
charArray = [charArray; tline(1:250)];
lineCounter = lineCounter + 1;
end
fclose(fid);
% Display in command window.
charArray
Of course you can get rid of the display lines (fprintf, etc.) if you want.
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Joseph Cheng
on 2 Apr 2014
Edited: Joseph Cheng
on 2 Apr 2014
simple method
fid = fopen('example.txt','r');
line = fgetl(fid);
spaces = strfind(line,' ');
line(spaces)=0;
x=line(:);
y=hex2dec(x)';
y(spaces)=NaN;
this is just an example but given the line of text use strfind(line,' ') to find the spaces. Note these indexes to be replaced by NaNs, make the spaces 0 and transpose it to a 250x1 array such that hex2dec will convert each into a number, then replace the index of the found spaces to NaN.
I used hex2dec as i noticed in your example you have a 'C' in there. So unless it was a typo its a hex number? if it is a typo then just use str2num or str2double instead
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Ammar
on 3 Apr 2014
Edited: Ammar
on 3 Apr 2014
4 Comments
Joseph Cheng
on 3 Apr 2014
use my method i had and modify it.
fid = fopen('example.txt','r');
line = fgetl(fid);
spaces = strfind(line,' ');
spaces = [0 spaces length(line)+1];
cellpos = 1;
for i=1:length(spaces)-1
portion = line(spaces(i):spaces(i+1)-1);
if portion ==' '
blah{cellpos}=NaN;
else
blah{cellps}=portion;
end
Azzi Abdelmalek
on 4 Apr 2014
Ammar, this is considered as an answer, you can add comments by clicking on [comment on this answer]* or create a new question
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