...the y differance squared i.e.
P1(x,y)
P2(x,y)
a=P1.x-P2.x ' dont worry about using ABS as the square we need is positive
b=P1.y-P2.y
|V|=sqrt(a*a+b*b)
note the angle of travel might be needed this is achieved using the Atn2 function
angle=Atn2(b,a)
hope this helps essentially it is...