I am getting an incorrect output when I try to remove elements using logical indexing

Hi

I am having an issue using logical indexing. I have a variable time which I imported into MATLAB from a .txt file.

I create a column vector dt=diff(time), which contains mostly one value, 0.01. I need to find elements that do not equal 0.01 and remove them e.g. time(dt~=0.01)=[]. However, MATLAB's logical indexing seems to have a problem with this in that it returns an incorrect value for most elements. E.g.

>> dt(3)

ans =

0.0100

>> find(dt==0.01)

ans =

     1
     2

As you can see the element 3 of dt is equal to 0.01, yet find only recognises the first two elements as being equal to 0.01. When I view the values of dt, if I delete one of the zeros after the 1 in element, this seems to fix the problem.

Can anyone shed any light on to why this is happening, and more importantly how I can fix it?

Thanks

Answer 1

[Image Analyst]

Well we can't really see because your input data is not attached. However this looks like it's perfectly explained by the FAQ.

[Joe]

Thanks, that seems to be the issue.