Stuart’s MATLAB Videos

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Using logical indexing to plot points meeting a specific criteria only.

Posted by Doug Hull,

If you have a vector of coordinate for a set of points, you might want to differentiate those points. To do that a concept called logical indexing will help you pull out a subset of those points easily. Here is a quick example (See the second video for more details)

 >> L = logical([0 1 0 1])
 L =
      0     1     0     1
 >> a = [1 2 3 4]
 a =
      1     2     3     4
 >> a(L)
 ans =
      2     4

The above video made practical use of logical indexing. The video below shows logical indexing in a more academic treatment.