how to code for this problem??

i have Names with subject marks as labels(column wise) and values(double) in excel file,like NAME SUBJECT_1 SUBJECT_2.....upto SUBJECT_50.

but for some analysis,i need to fetch few subject values(15 subjects) with respect to name. my selected subjects labels will be given in header.txt.(wt ever subject label i give in this header.txt,my program should fetch that subject column data's alone and store in separate file). any help or suggestion for this concept??..............need help here

Answer 1

[Image Analyst]

Try this (untested):

[num, txt, raw] = xlsread(fullFileName); % Read in Excel file.
[rows, columns] = size(txt);
% Get random numbers
filesToSelect = randperm(rows, 15);
% Select 15 random filenames from the whole list.
selectedStrings = txt(filesToSelect, :);

% Now open headers.txt and pull out those
fid = fopen('headers.txt');
tline = fgetl(fid);
counter = 1;
while ischar(tline)
  disp(tline)
  % Get next line.
  tline = fgetl(fid);
  % Save it as a header line.
  headers{counter} = tline;
end
% Extract just those we want.
headers = headers{selectedStrings);
fclose(fid);

[sandy]

its not working..randperm() syntax showing error..i couldnt go further..

[Image Analyst]

You must have a really old version of MATLAB. Try this instead:

filesToSelect = randperm(rows); % Get all numbers scrambled.
filesToSelect = filesToSelect (1 : 15); % Take 15 of them.

[sandy]

thanks...what i need is..if i give the names of required subject names like (ex:SUBJECT_1 SUBJECT_4 SUBJECT_9 SUBJECT_23) in a header.txt(4*1) file,it should compare with the headers (ex:SUBJECT_1 SUBJECT_2.. SUBJECT_50)which is in sample.xlsx(200*50) (below each SUBJECT many values will be present(column wise))and copy the matched subjects values to another variable as(200*4)

[Image Analyst]

Use ismember().

[sandy]

thanks..using ismember() can find which column matched subject,but how to get the values below (only for matched subjecdt name)??

[Image Analyst]

Yes. It works on cell arrays of strings. Just look over the documentation and try it.

ca = {'SUBJECT_1'; 'SUBJECT_4'; 'SUBJECT_9'; 'SUBJECT_23'; 'SUBJECT_4'}
lookingFor = 'SUBJECT_4'
matchingLogicalIndexes = ismember(ca, lookingFor)
matchingRowNumbers = find(matchingLogicalIndexes)

In the command window:

ca = 
    'SUBJECT_1'
    'SUBJECT_4'
    'SUBJECT_9'
    'SUBJECT_23'
    'SUBJECT_4'
lookingFor =
SUBJECT_4
matchingLogicalIndexes =
     0
     1
     0
     0
     1
matchingRowNumbers =
     2
     5