Is numpy included on the Raspberry Pi

Yes it is.
My Raspberry came with Raspbian Wheezy installed.

At the command line I started python,

then entered:

>>> from numpy import *
>>> a = arange(15).reshape(3, 5)
>>> a

 Which gave:

array([[ 0,  1,  2,  3,  4],
       [ 5,  6,  7,  8,  9],
       [10, 11, 12, 13, 14]])
>>>