petsc-3.14.6 2021-03-30

DMPlexCreateBasisRotation

Create an internal transformation from the global basis, used to specify boundary conditions and global solutions, to a local basis, appropriate for discretization integrals and assembly.

Synopsis

#include "petscdmplex.h"   
PetscErrorCode DMPlexCreateBasisRotation(DM dm, PetscReal alpha, PetscReal beta, PetscReal gamma)

Input Parameters

	dm	- The DM
	alpha	- The first Euler angle, and in 2D the only one
	beta	- The second Euler angle
	gamma	- The third Euler angle

Note: Following https://en.wikipedia.org/wiki/Euler_angles, we will specify Euler angles by extrinsic rotations, meaning that

we rotate with respect to a fixed initial coordinate system, the local basis (x-y-z). The global basis (X-Y-Z) is reached as follows

$ The XYZ system rotates about the z axis by alpha. The X axis is now at angle alpha with respect to the x axis. $ The XYZ system rotates again about the x axis by beta. The Z axis is now at angle beta with respect to the z axis. $ The XYZ system rotates a third time about the z axis by gamma.

Level

developer

Location