strfind issue
3 views (last 30 days)
Show older comments
Hi,
I have a filename (including whole path) as a string with directories separated by / e.g. root/folder/file.
I am using strfind to find the slashes as follows and to give an index array of the position of the / symbols, :
% Find all occurances of the string '/'
[no_slash] = strfind ( line, '/' );
and then trying to extract the filename as a string as follows:
% Extract the case number:
caseNo = ( [no_slash(3)+1 : no_slash(3)+4] );
I get NaN returned and I don't know why! If anyone has an idea or an alternative method then it would be much appreciated!!
Thanks,
Robbie
0 Comments
Accepted Answer
Matt Tearle
on 29 Nov 2011
As Daniel says, there must be more going on. Can you copy the code directly? strfind returns the indices; if there are no matches, it returns []. Hence, if line was 'root/folder/file', strfind(line,'/') returns [5,12].
So in this case you'd get an indexing (out of bounds) error on the next line. If there was three slashes in the string, you'd get a vector like [13, 14, 15, 16].
Are you perhaps trying to extract a portion of the string and str2num it? In which case, you want
caseNo = str2double(line(no_slash(3)+1 : no_slash(3)+4))
(Note: if you leave out the line in the above command, you get NaN. Or if line isn't a string.)
2 Comments
More Answers (1)
Daniel Shub
on 29 Nov 2011
The only way
[no_slash(3)+1 : no_slash(3)+4]
can be equal to NaN is if no_slash(3) is equal to NaN. You are not showing us something important because I am pretty sure that strfind does not return NaN.
All that said fileparts might help you out...
doc fileparts
3 Comments
Daniel Shub
on 29 Nov 2011
What is no_slash equal to? Can you check that line is also a string. Please post a MWE with what line needs to be to get the error?
See Also
Categories
Find more on Characters and Strings 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!