problem with the setdiff function

3 views (last 30 days)
alex
alex on 17 Mar 2014
Commented: alex on 17 Mar 2014
Hello!
i have a problem here
A = 2:.1:15
B=[9.4000 10.4000]
C=setdiff(A,B)
the elements 9.4000 and 10.4000 are still in the C
however,if B=[9.3000 10.3000] then the setdiff works fine,and the elements are not in the C.
any idea why this happens?

Accepted Answer

Azzi Abdelmalek
Azzi Abdelmalek on 17 Mar 2014
Edited: Azzi Abdelmalek on 17 Mar 2014
  3 Comments
Azzi Abdelmalek
Azzi Abdelmalek on 17 Mar 2014
Edited: Azzi Abdelmalek on 17 Mar 2014
Use some tolerance
A = 2:.1:15
B=[9.4000 10.4000 1000]
tol=0.0001
s=abs(bsxfun(@minus,A',B))<tol
[ii,jj]=find(s==1);
A(ii)=[]
alex
alex on 17 Mar 2014
thank you very much!
it works excellent!

Sign in to comment.

More Answers (1)

Jos (10584)
Jos (10584) on 17 Mar 2014
A = 2:.1:15
B = [9.4000 10.4000]
D = 2 ; % number of digits that should match (e.g. 1.231 = 1.229)
C = setdiff(round(A*10^D),round(B*10^D)) ./ (10^D)

Categories

Find more on Structures 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!