ganesh,try the following......
U can type "help rotate" in MATLAB to get help. here is the help content:
ROTATE Rotate objects about specified origin and direction.
ROTATE(H,[THETA PHI],ALPHA) rotates the objects with handles H
through angle ALPHA about an axis described by the 2-element
direction vector [THETA PHI] (spherical coordinates).
All the angles are in degrees. The handles in H must be children
of the same axes.
THETA is the angle in the xy plane counterclockwise from the
positive x axis. PHI is the elevation of the direction vector
from the xy plane (see also SPH2CART). Positive ALPHA is defined
as the righthand-rule angle about the direction vector as it
extends from the origin.
ROTATE(H,[X Y Z],ALPHA) rotates the objects about the direction
vector [X Y Z] (Cartesian coordinates). The direction vector
is the vector from the center of the plot box to (X,Y,Z).
ROTATE(...,ORIGIN) uses the point ORIGIN = [x0,y0,y0] as
the center of rotation instead of the center of the plot box.
See also SPH2CART, CART2SPH.
OR
Rotating a vector by theta means multiplying this by a unit vector with the angle theta.
See if the below link helps
Rotation (mathematics) - Wikipedia, the free encyclopedia
ALL THE BEST....................