Matlab, how to filter a numeric vector by a condition?

Question

In Matlab, I have a vector, X, that contains N real values:

• 0.001
• 0.003
• 0.006
• 0.009
• 0.007
• 0.006

I would like to create a new vector, Xb, that contains all the M values of X that are less than 0.005 (M <= N). How could I do it?

I've tried with:

Xb = X<0.005

but it gives me a vector of N values 0s or 1s.

Thanx

Answer 1

>> Xb = X(X < 0.005)

Xb =

    0.0010    0.0030

Answer 2

What you did with the code Xb=X<0.005 was to create a mask. Simply put, it tells you which values are less than 0.005, but with no sorting of the list. What you want is to sort the list by the mask, which can be done as jlrcowan has suggested.