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reset quats for ellipsoids for general <-> restriced triclinic

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This commit is contained in:
Steve Plimpton
2023-11-03 14:52:41 -06:00
parent 7a148688d5
commit 6fe6395ab2
5 changed files with 109 additions and 3 deletions
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25
src/math_extra.cpp
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@ -362,6 +362,29 @@ void exyz_to_q(double *ex, double *ey, double *ez, double *q)
qnormalize(q);
}
/* ----------------------------------------------------------------------
create unit quaternion from a rotation matrix
just a wrapper on exyz_to_q()
ex,ey,ez are columns of a rotation matrix
------------------------------------------------------------------------- */
void mat_to_quat(double mat[3][3], double *q)
{
double ex[3],ey[3],ez[3];
ex[0] = mat[0][0];
ex[1] = mat[1][0];
ex[2] = mat[2][0];
ey[0] = mat[0][1];
ey[1] = mat[1][1];
ey[2] = mat[2][1];
ez[0] = mat[0][2];
ez[1] = mat[1][2];
ez[2] = mat[2][2];
MathExtra::exyz_to_q(ex,ey,ez,q);
}
/* ----------------------------------------------------------------------
compute space-frame ex,ey,ez from current quaternion q
ex,ey,ez = space-frame coords of 1st,2nd,3rd principal axis
@ -417,6 +440,7 @@ void quat_to_mat(const double *quat, double mat[3][3])
/* ----------------------------------------------------------------------
compute rotation matrix from quaternion conjugate
quat = [w i j k]
similar logic to quat_to_mat()
------------------------------------------------------------------------- */
void quat_to_mat_trans(const double *quat, double mat[3][3])
@ -647,5 +671,4 @@ void tribbox(double *h, double radius, double *dist)
/* ---------------------------------------------------------------------- */
}