Importing periodic data with textscan and fgetl?

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Here's a subset of the data I'm trying to import into MATLAB:
Time = 0.50734E-01
X Y Z EP_g
23.865 25.227 -0.50000 0.56828
24.135 25.227 -0.50000 0.56839
23.865 25.500 -0.50000 0.56834
24.135 25.500 -0.50000 0.56831
Time = 1.00059E-01
X Y Z EP_g
23.865 25.227 -0.50000 0.56828
24.135 25.227 -0.50000 0.56840
23.865 25.500 -0.50000 0.56835
24.135 25.500 -0.50000 0.56832
I am trying to import this data using textscan and fgetl but have been having trouble. The problem is those pesky lines between each subset.
The column on the far right (EP_g) is the only thing I'm really interested in. By the time I'm done, I just want a matrix with the transpose of the EP_g column along the rows, i.e.,
data =
0.56828 0.56839 0.56834 0.56831
0.56828 0.56840 0.56835 0.56832
My attempt at a solution:
fid=fopen(file)
while ~feof(fid)
tmp=textscan(fid,'%f%f%f%f','Headerlines',5)
for j=[1:2]
fgetl(fid)
end;
end;
fclose(fid);
I would appreciate any guidance or help you can give me. Many thanks!

Accepted Answer

William
William on 21 Nov 2012
I managed to get it to work by using only the textscan function. I had seen an example using fgetl and I thought I needed it for this application, but it turns out I didn't.
fid=fopen('n90deg'); % Open file
c=1; % Initialize counter
while ~feof(fid); % Run until end of file
tmp=textscan(fid,'%f%f%f%f','Headerlines',2); % Omit first two lines every
% time
n90deg(c,:)=tmp{4}'; % Store the last cell as a row in new matrix
c=c+1; % Add to counter and repeat above steps
end
fclose(fid);
Hopefully someone else will find this useful.

More Answers (2)

Azzi Abdelmalek
Azzi Abdelmalek on 21 Nov 2012
fid = fopen('file.txt');
line1 = fgetl(fid);
res=line1;
while ischar(line1)
line1 = fgetl(fid);
res =char(res,line1)
end
fclose(fid);
  3 Comments
Azzi Abdelmalek
Azzi Abdelmalek on 21 Nov 2012
Edited: Azzi Abdelmalek on 21 Nov 2012
fid = fopen('data3.txt');
line1 = fgetl(fid);
res=line1;
while ischar(line1)
line1 = fgetl(fid);
res =char(res,line1)
end
fclose(fid);
n=size(res,1)-1
ii=0;
for k=1:6:n
ii=ii+1
data{ii}=str2num(res(k+2:k+5,:))
t=regexp(res(k,:),'=','split')
t1{ii}=str2num(t{2})
end
William
William on 21 Nov 2012
Yes, that makes much more sense. I was trying str2mat and str2cell but didn't try str2num. Thank you very much Azzi!

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Y. J.
Y. J. on 7 May 2018
Hey guys i have a simmilar problem. My File looks like this:
06.12.2099 13:50:37
502C43 ZU152323
Radial
f acceleration
b kg
Example value
1/3 t = 0 s
+0.0000e+00 +1.4013e-03
+1.4648e+02 +2.6760e-05
+2.9297e+00 +2.1846e-06
+4.3945e+04 +1.5014e-10
+5.8594e+00 +7.3407e-40
+7.3242e+06 +6.7897e-06
2/3 t = 0.682667 s
+0.0000e+00 +1.4013e-03
+1.4648e+02 +2.6760e-05
+2.9297e+00 +2.1846e-06
+4.3945e+04 +1.5014e-10
+5.8594e+00 +7.3407e-40
+7.3242e+06 +6.7897e-06
3/3 t = 0.682667 s
+0.0000e+00 +1.4013e-03
+1.4648e+02 +2.6760e-05
+2.9297e+00 +2.1846e-06
+4.3945e+04 +1.5014e-10
+5.8594e+00 +7.3407e-40
+7.3242e+06 +6.7897e-06
And i read the two value columns like this:
fmt = '%f %f';
fid=fopen('Example.txt,'r');
k = 1;
while (~feof(fid))
k = k+1;
c(k-1,1) = textscan(fid,fmt,'collectoutput',true,'HeaderLines',7);
end
fid=fclose(fid);
This works fine and he stores me the Values for each time separately. But I need also the time value after "t = ". And it should be saved in my cell also. at the moment i get a 3x1 cell (in this case).
Thank you in advance.

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