Rotation axis and angle of rotation given a rotation matrix {Directional}

Rotation axis and angle of rotation given a rotation matrix

Description

Given a 3 x 3 rotation matrix, the angle and the axis of rotation are calculated.

Usage

Arotation(A)

Arguments

A

A 3 x 3 rotation matrix.

Details

If the user does not supply a rotation matrix a message will appear.

Value

A list including:

angle

The angle of rotation expressed in degrees.

axis

The axis of rotation. A vector of two components, latitude and longitude, expressed in degrees.

Author(s)

Michail Tsagris.

R implementation and documentation: Michail Tsagris [e-mail] and Giorgos Athineou <[e-mail]>.

References

Course webpage of Howard E. Haber. http://scipp.ucsc.edu/~haber/ph216/rotation_12.pdf

Ted Chang (1986). Spherical Regression. Annals of Statistics, 14(3): 907–924.

See Also

rot.matrix, rotation, rsop

Examples

ksi <- c(25.31, 24.29)
theta <- 2.38
A <- rot.matrix(ksi, theta, rads = FALSE)
A
Arotation(A)