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     COS(9.3)                                                 COS(9.3)

          cos, sin, atan2, sqrt, norm - integer math functions

          int cos(d) int d;

          int sin(d) int d;

          int atan2(x, y) int x, y;

          int norm(x, y, z) int x, y, z;

          int sqrt(x) long x;

          Cos and Sin return scaled integer approximations to the
          trigonometric functions.  The argument values are in
          degrees.  The return values are scaled so that cos(0)=1024.
          Therefore, to calculate, for example, the mathematical
          expression x=x0*cos(d), the multiplication must be scaled:

               x=muldiv(x0, cos(d), 1024).

          Atan2 returns the approximate arc-tangent of y/x.  The
          return value is in integral degrees.  The approximation is
          poor; the error may be as large as two degrees.

          Sqrt returns the 16-bit signed integer closest to the square
          root of its 32-bit signed argument.

          Norm returns the Pythagorean length of the three-vector (x,
          y, z).

          Atan2(0, 0) and sqrt(0) return 0.  Norm does not protect
          against overflow.