AngleBetweenVectors.bas

type coord
    x as integer
    y as integer
end type

function dotProduct(u as coord, v as coord) as double
    return (u.x * v.x) + (u.y * v.y)
end function

function norm(u as coord) as double
    return sqr((u.x*u.x) + (u.y*u.y))
end function

dim as coord u = type(2, 3)
dim as coord v = type(5, 1)

print dotProduct(u, v)
print norm(u), norm(v)

print acos(dotProduct(u, v)/(norm(u)*norm(v)))

sleep