Problem with ismember function
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Dear all, Hello,
I am writing a simple function of ismember to check if an element in one matrix matches the one in another matrix, however it returns 0, although I am sure the value matches. Assume I have a array of "omega". The third element is equal to 0.1047. And I have another matrix "wt", with first element, 0.1047 and when I write
z=ismember(omega,wt,'rows')
it returns a zero at z(3). Hence, I have:
omega(3)=0.1047;
wt(1)=0.1047;
I expect:
z(3)=1;
but it gives:
z(3)=0;
I must say that it returns 1 for omega(4) which is 0.1571 and equals the wt(2).
Thank you for your help.
Cheers,
2 Comments
Jan
on 26 Jun 2017
Test this manually:
omega(3) - wt(1)
Is this really exactly 0? Note that the limited output of numbers in Matlab's command window let 0.1047 and 0.104699999999999 appear equally, althout the numbers are different.
Stephen23
on 26 Jun 2017
"Problem with ismember function"
There is no problem with ismember. You need to learn about the practical limits of floating point numbers:
And some external links on this topic:
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