main/src/georegression/geometry/ConvertRotation3D_F64.java
private static DMatrixRMaj rotationAboutAxis(int axis, double angle, DMatrixRMaj R ) {
		switch( axis ) {
			case 0:
				return ConvertRotation3D_F64.rotX( angle, R );

			case 1:
				return ConvertRotation3D_F64.rotY( angle, R );

			case 2:
				return ConvertRotation3D_F64.rotZ( angle, R );

			default:
				throw new IllegalArgumentException( "Unknown which" );
		}
	}
private static DMatrixRMaj rotationAboutAxis(int axis, double angle, DMatrixRMaj R ) {
		switch( axis ) {
			case 0:
				return ConvertRotation3D_F64.rotX( angle, R );

			case 1:
				return ConvertRotation3D_F64.rotY( angle, R );

			case 2:
				return ConvertRotation3D_F64.rotZ( angle, R );

			default:
				throw new IllegalArgumentException( "Unknown which" );
		}
	}
Creates a rotation matrix about the specified axis.

@param axis  0 = x, 1 = y, 2 = z
@param angle The angle it is rotated by in radians.
@return The 3 by 3 rotation matrix.