MATLAB: How to read text file and to ignore the first 10 rows and to take only the 4rth and 5th columns

dlmreadimportdatatextscan

how to read text file and to ignore the first 10 rows and to take only the 4rth and 5th columns? from this file: http://iopscience.iop.org/0266-5611/17/6/301/media/dielTM_dec4f.exp

i tried to use textscan but i don't really understand how to and it looks a bit complicated

any other solution or how to do this?

Best Answer

Try

    cac = textscan( fid, '%*f%*f%*f%f%f%*f%*f', 'Headerlines', 10 );

Doc says: &nbsp %* &nbsp Skip the field. textscan does not create an output cell for any field that it skips.

That's not too complicated!

&nbsp

"any other solution or how to do this?" &nbsp None less complicated than textscan - AFAIK

Related Solutions

MATLAB: Find the rth “0” in specific columns in a matrix

cols = [1 3 4 6 7]; % selected columns.

num_zeros = [3,4];% The ordinal number "0" in each selected column.

M_nozeros = cumsum(~M).*~M;
[~,ii] = ismember(M_nozeros(:,cols),num_zeros);
[k,jj] = ndgrid(1:size(M,1),cols);
idx = [k(:),jj(:)];
out = accumarray(ii(:) + 1,1:numel(ii),[],@(x){idx(x,:)});
out = out(2:end);

out - cell array, here each cell corresponds to the ordinal number "0" ( num_zeros), each cell contains a double matrix: rows are the ordinal number of the row containing zero, the columns correspond to cols.

Use:

>> cols = [1 3 4 6 7]; % selected columns.
num_zeros = [3,4];% The ordinal number "0" in each selected column.
M = rand(15,10) < .25
M =
  15×10 logical array
   0   0   0   0   1   0   0   0   0   0
   0   0   0   0   0   0   1   0   0   1
   1   0   0   1   1   0   0   0   0   1
   0   0   0   1   0   0   1   0   0   0
   0   0   0   0   1   0   0   0   0   0
   0   0   0   1   1   0   0   0   0   0
   0   1   0   0   0   1   0   0   0   0
   0   1   0   0   0   0   0   0   1   1
   1   0   1   0   0   1   0   0   0   0
   0   0   0   0   0   0   0   0   0   0
   1   0   0   0   0   0   1   0   0   0
   0   0   0   1   1   1   1   1   0   1
   0   0   0   0   0   0   1   0   0   0
   0   0   1   0   0   1   1   0   0   0
   1   0   0   0   0   0   1   0   0   0
>> 
>> M_nozeros = cumsum(~M).*~M;
[~,ii] = ismember(M_nozeros(:,cols),num_zeros);
[k,jj] = ndgrid(1:size(M,1),cols);
idx = [k(:),jj(:)];
out = accumarray(ii(:) + 1,1:numel(ii),[],@(x){idx(x,:)});
out = out(2:end);
>> 
>> out{:}
ans =
     4     1
     3     3
     3     6
     5     4
     5     7
ans =
     4     6
     5     1
     6     7
     4     3
     7     4
>>

MATLAB: How to scan text

The frequencies are integers in the third column. This code works for the first file and should work for both:

fidi = fopen('rectTE_8f.exp');
d = textscan(fidi, '%d%d%d%f%f%f%f', 'Headerlines',10, 'Delimiter','\n','CollectOutput',1);
frqs = d{1}(:,3);

The ‘frqs’ variable is your vector of frequencies.

If you want a vector of only the frequencies on the 5th line, you can get them easily enough with:

ufrqs = unique(frqs);

It will give you a vector of the unique frequencies in the vector.

Best Answer

Related Solutions

MATLAB: Find the rth “0” in specific columns in a matrix

MATLAB: How to scan text

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