GEOM200 Rotation matrices

The relative position of a volume inside its mother is expressed in GEANT by a translation vector and a rotation matrix which are arguments of the routines GSPOS and GSPOSP. The rotation matrix expresses the transformation from the Mother Reference System to the Daughter Reference System.

A rotation matrix is described to GEANT by giving the polar and azimuthal angles of the axes of the DRS ($x\text{'},\; y\text{'},\; z\text{'}$ ) in the MRS via the routine GSROTM.

CALL GSROTM (IROT,THETA1,PHI1,THETA2,PHI2,THETA3,PHI3)

IROT

( INTEGER) number of the rotation matrix;

THETA1

( REAL) polar angle for axis $x\text{'}$ ;

PHI1

( REAL) azimuthal angle for axis $x\text{'}$ ;

THETA2

( REAL) polar angle for axis $y\text{'}$ ;

THI2

( REAL) azimuthal angle for axis $y\text{'}$ ;

THETA3

( REAL) polar angle for axis $z\text{'}$ ;

PHI3

( REAL) azimuthal angle for axis $z\text{'}$ .

Note: the angles THETA and PHI must be given in degrees.

• Examples of use