Extracting coordinates from a text file
6 views (last 30 days)
Show older comments
Pelajar UM
on 25 Aug 2022
Commented: Walter Roberson
on 25 Aug 2022
I have a text file that contains various info. I am interested in the coordinates that come in the following format:
<SERIES_2D UniqueID="0" Name="Band energy" NumPoints="1760">
<POINT_2D XY="0.1526777587356064,-18.83713650553515"/>
<POINT_2D XY="0.2259585473519713,-18.77591633509903"/>
<POINT_2D XY="0.2992393359683362,-18.68414023009788"/>
<POINT_2D XY="0.3629792736759856,-18.65734926254393"/>
<POINT_2D XY="0.4267192113836351,-18.60265900778901"/>
<POINT_2D XY="0.5,-18.62938793338875"/>
</SERIES_2D>
where the value of NumPoints (in this case 1760) can vary.
atextfile = fileread ('textfile.txt');
a=strfind (atextfile,'POINT_2D XY="');
b= atextfile(:,a);
and b returns PPPPPPP... So this is clearly not working as intended.
I want to take the XY coordinates between <SERIES_2D UniqueID="0" Name="Band energy" NumPoints="1760"> and </SERIES_2D> and put them in an array.
0 Comments
Accepted Answer
Walter Roberson
on 25 Aug 2022
parts = regexp(atextfile, 'XY="(?<X>[^,]+),(?<Y>[^"]+)', 'names');
X = str2double({parts.X});
Y = str2double({parts.Y});
Unless, that is, there are other XY= in the file that need to be excluded.
2 Comments
Walter Roberson
on 25 Aug 2022
sections = regexp(atextfile, '^<SERIES_2D.*?SERIESL_2D>', 'match');
parts = regexp(sections, 'XY="(?<X>[^,]+),(?<Y>[^"]+)', 'names');
Xs = cellfun(@(C) str2double({C.X}), parts, 'uniform', 0);
Ys = cellfun(@(C) str2double({C.Y}), parts, 'uninform', 0);
This code will break up the input into series, and then extract the X and Y within each series. The output will be a cell array Xs and a cell array Ys, each with one entry per section, containing the coordinates for that section.
More Answers (0)
See Also
Categories
Find more on Other Formats in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!