MATLAB: Extract values and save them as unique txt files

extracttxtfilesunique

Hi, I have a vector and what to extract the unique values of the first column and save those as separate txt file with the same ID as unique ID. Thanks a lot! For example A:

A dataset:

21  723204  12
21  723204  10.5000000000000
21  723204  13.5000000000000
21  723292  20
21  723356  21
21  723447  19
21  723483  17
21  723503  16
21  723503  11
22  723572  11
22  723594  12.5000000000000
22  723621  16.5000000000000
22  723663  16
23  723692  19
23  723720  26
23  723720  32
23  723783  22
%end

and result should be: 21.txt, 22.txt, 23.txt with e.g. 23.txt is:

723692  19
723720  26
723748  32
723783  22
and so on...(so without first column in the resulting txt file).

so far I did :

[C,ia,ic] = unique(A(:,1),'rows')
rows21 = A(C==21, :); % but I do not want to this separately since it takes a lot of time. I would like to do with for loop if possible so I create automatically txt files? thanks a lot!

Best Answer

This works:

data = dlmread('text.txt')
% Get unique values in column 1
uniqueValues = unique(data(:, 1))'
for k = uniqueValues
  fullFileName = fullfile(pwd, sprintf('%d.txt', k))
  rowsToWrite = data(:, 1) == k;
  dlmwrite(fullFileName, data(rowsToWrite, 2:end), 'delimiter', ' ', 'precision','%g');
end

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MATLAB: App Designer: Create drop down list from unique table values

This works (although it hurts to look at)...

unique_values = cellstr(num2str(table2array(unique(t(:,1)))));
app.DropDown.Items = unique_values;

MATLAB: Combine strings and doubles and export to .txt

You can do this quite easily without any loops:

C1 = {'Node coordinates and Elements','Coordinates'};
C2 = {'End Coordinates','','Elements'};
C3 = {'End Elements'};
A = [1,50,20.5000000000000,20;2,50,20.5000000000000,-20;3,50,20.5000000000000,6.66666666666670;4,50,20.5000000000000,-6.66666666666670;5,-50,20.5000000000000,-20;6,37.5000000000000,20.5000000000000,-20;7,25,20.5000000000000,-20;8,12.5000000000000,20.5000000000000,-20;9,0,20.5000000000000,-20;10,-12.5000000000000,20.5000000000000,-20]
B = [1,27,32,33;2,27,26,32;3,24,29,30;4,24,23,29;5,37,36,34;6,37,3,36;7,39,35,14;8,39,29,35]
% Define matrix formats:
fmtA = [repmat(' %9.4f',1,size(A,2)),'\n'];
fmtB = [repmat(' %5d',1,size(B,2)),'\n'];
% Export data to file:
[fid,msg] = fopen('temp2.txt','wt');
assert(fid>=3,msg)
fprintf(fid,'%s\n',C1{:})
fprintf(fid,fmtA,A.')
fprintf(fid,'%s\n',C2{:})
fprintf(fid,fmtB,B.')
fprintf(fid,'%s\n',C3{:})
fclose(fid);

Giving (also attached as a file):

Node coordinates and Elements
Coordinates
    1.0000   50.0000   20.5000   20.0000
    2.0000   50.0000   20.5000  -20.0000
    3.0000   50.0000   20.5000    6.6667
    4.0000   50.0000   20.5000   -6.6667
    5.0000  -50.0000   20.5000  -20.0000
    6.0000   37.5000   20.5000  -20.0000
    7.0000   25.0000   20.5000  -20.0000
    8.0000   12.5000   20.5000  -20.0000
    9.0000    0.0000   20.5000  -20.0000
   10.0000  -12.5000   20.5000  -20.0000
End Coordinates
Elements
     1    27    32    33
     2    27    26    32
     3    24    29    30
     4    24    23    29
     5    37    36    34
     6    37     3    36
     7    39    35    14
     8    39    29    35
End Elements

Note that I followed the format of the example output text that you wrote in your answer, where you used multiple space characters as the delimiter. In your later comments you used horizontal tab characters as the delimiter, making your question and comments inconsistent.

I do not know of any sprintf format that prints four decimal places for all values except zero.

Best Answer

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MATLAB: App Designer: Create drop down list from unique table values

MATLAB: Combine strings and doubles and export to .txt

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