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RT 3A - RoTate - volume, around arbitrary center

(07/22/97)

PURPOSE

Rotates a volume around an arbitrary center by the three Eulerian angles.

SEE ALSO

RT [RoTate - image or volume, use average as background]
RT 3 [RoTate - volume, slow]
RT 3A [RoTate - volume, around arbitrary center]
RT 90 [RoTate - image or volume, by 90, 180, or 270 degrees]
RT B [RoTate - image or volume, supply background]
RT C [Rotate - image, around arbitrary center, for small files]
RT M [Rotate - image or volume, use minimum as background]
RT SQ [RoTate - image or volume, shift, use quadratic interpolation]

USAGE

.OPERATION: RT 3D

.INPUT FILE: PIC001
[Enter the name of the file to be rotated.]

.OUTPUT FILE: ROT001
[Enter the name of the file where the rotated volume is to be stored.]

.Phi, Theta: 10.5,13.7
[Enter the rotation angles Phi (around Z) and Theta (around the new Y after the first rotation by Phi).]

.Psi: 45.8
[Enter the third rotation angle (around the new Z)].

.Center of rotation NX, NY: 12,27
[Enter x,y coordinates of a center of rotation. Volume extends in x from 1 to NSAM and in y from 1 to NROW.]

.Center of rotation NZ: 55
[Enter z coordinate of a center of rotation. Volume extends in a from 1 to NSLICE.]

NOTES

  1. Program reads first volume into the memory - larger volumes may not fit. In this case use 'RT 3' instead. Unfortunately 'RT 3' gives slightly incorrect results and does not use the proper interpolation scheme and has sign of theta reversed.

  2. Tri-linear interpolation scheme is used.

  3. Non-matching points are replaced by the average.

  4. All the rotations are done clockwise.

  5. Rotation matrix used:
     
              R = R(psi) * R(theta) * R(phi) 
               c  s  0        c  0 -s      c  s  0 
              -s  c  0    *   0  1  0   * -s  c  0 
               0  0  1        s  0  c      0  0  1 
    

  6. In the corners, old values are left.

  7. Implemented by Paul Penczek.

SUBROUTINES

ROTAS3, ROTS3, BLDR

CALLER

UTIL3

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