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7.5 Conversions

•       SUBROUTINE SPHCAR(OBSPH, PVU, OBS, VERTI)
        REAL OBS(3), OBSPH(3), PVU(3)
        INTEGER VERTI
  

  converts OBSPH, in spherical coordinates  (angle w.r.t. 0X, elevation w.r.t. X0Y and distance), into OBS, in Cartesian coordinates (x,y,z).
  

  Input:
  

  OBSPH: observer in spherical coordinates;

  PVU: point viewed (x,y,z);

  VERTI: vertical 1=0x, 2=0y, 3=0z.
  

  Output:
  

  OBS: observer in Cartesian coordinates.
  

•       SUBROUTINE CARSPH(OBS, PVU, OBSPH ,VERTI)
        REAL OBS(3), OBSPH(3), PVU(3)
        INTEGER VERTI
  

  converts OBS, in  Cartesian coordinates (x,y,z), into OBSPH, in spherical coordinates (a/0x, e/x0y, distance).
  

  Input:
  

  OBS: observer in Cartesian coordinates (x,y,z);

  PVU: point viewed (x,y,z);

  VERTI: vertical 1=0x, 2=0, 3=0z.
  

  Output:
  

  OBSPH: observer in spherical coordinates.