Directional (version 2.2)

Rotation matrix to rotate a spherical vector along the direction of another: Rotation matrix to rotate a spherical vector along the direction of another

Description

A rotation matrix is calcualted to rotate a spherical vector along the direction of another.

Usage

rotation(a, b)

Arguments

a

The initial spherical unit vector.

b

The target spherical unit vector.

Value

A 3 x 3 matrix with a rotation matrix.

Details

The function calcualtes a rotation matrix given two vectors. This rotation matrix is the connection between the two spherical only, vectors.

References

G. J. A. Amaral, I. L. Dryden & Andrew T. A. Wood (2007). Pivotal Bootstrap Methods for k-Sample Problems in Directional Statistics and Shape Analysis. Journal of the American Statistical Association, 102(478): 695-707.

See Also

Arotation, rot.matrix, lambert, lambert.inv, rsop

Examples

a <- rnorm(3)
a <- a/sqrt(sum(a^2))
b <- rnorm(3)
b <- b/sqrt(sum(b^2))
A <- rotation(a, b)
A
a  ;  b
a %*% t(A)