how to scan text

on those files:

http://iopscience.iop.org/0266-5611/17/6/301/media/rectTE_8f.exp

http://iopscience.iop.org/0266-5611/17/6/301/media/dielTM_dec4f.exp

on the 5th line there [are these] data:

# Number of frequencies : 8 (2, 4, 6, 8, 10, 12, 14, 16 GHz)
# Number of frequencies : 4 (4, 8, 12, 16 GHz)

i need to create a vector with those values i tried to locate the number 8 or 4 using textscan and to make a for loop n times to get those integers, but it didn't work, maybe there is something with the (,)

any suggestions?

Answer 1

[Star Strider]

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.

[Kobi]

thank you Star Strider, that was very helpful.

[Star Strider]

My pleasure!

Answer 2

[Guillaume]

You have to use low level io functions if you want to parse the header:

fid = fopen('rectTE_8f.exp', 'rt');
for l = 1:4
   fgetl(fid); %skip first four lines
end
numfreq = fscanf(fid, '# Number of frequencies : %d (');
frequencies = fscanf(fid, '%d, ', [1 numfreq]);
fgetl(fid); %get rest of line
for l = 6:10
   fgetl(fid); %skip rest of header
end
arr = textscan(fid, ...); %get rest of file with textscan
fclose(fid);

Answer 3

[dpb]

When you get to that line, either by headerlines or previously parsing if you need some of those data, then

n=cell2mat(textscan(fid,'# Number of frequencies : %d ('));  % read the number of freq's

Now you can build a format string using that value as--

fmt=['(' repmat('%d,',1,n-1) '%d GHz)'];
f=cell2mat(textscan(fid,fmt));