8.2.4.14} Generic Quadric. Code: QUA

      A QUA is a quadric surface defined by a 2nd degree equation F(x,y,z) = 0.
      Each QUA is defined by 10 numbers:
      A_xx, A_yy, A_zz, A_xy, A_xz, A_yz, A_x, A_y, A_z, A_0
      corresponding to the equation:
      A_xx x^2 + A_yy y^2 + A_zz z^2 + A_xy xy + A_xz xz + A_yz yz +
          + A_x x + A_y y + A_z x + A_0 = 0
      A QUA definition extends over two lines in default fixed format,
      and over 4 lines in high-accuracy body fixed format.

      Example in default fixed format:
 *...+....1....+....2....+....3....+....4....+....5....+....6....+....7..
   QUA   27    0.0025      0.04    0.0064       0.0       0.0       0.0
                0.055      0.64    0.0256    1.8881
 * (an ellipsoid centred at x = -11 cm, y = -8 cm, z = -2 cm, with
 * a semi-axis 20 cm long parallel to x, one 5 cm long parallel to y and
 * one 12.5 cm long parallel to z)

      The same example in high-accuracy body fixed format:
 *...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+.
   QUA   27                0.0025                  0.04                0.0064
                              0.0                   0.0                   0.0
                            0.055                  0.64                0.0256
                           1.8881

      The same body, described in free format:
 QUA  Elipsoid  0.0025 0.04 0.0064 0.0 0.0 0.0 0.055 0.64 0.0256 1.8881

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