Finding multiple locations in a vector

I was hoping someone could help, I am trying to use the find function to give me the location of the values of a vector in a larger vector.

ie

[a,b] = find(A==B);

where A is 300 by 1 and B is 20 by 1 but obviously I get an error because B is not a single value. Is there another function that I can use?

Answer 1

[Azzi Abdelmalek]

a=ismember(A,B)
b=find(a)

Answer 2

[Image Analyst]

You can use ismember() as long as they're integers or powers of two. If they're weird floating point numbers, see the FAQ: http://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F