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fixtan(3)                       Allegro manual                       fixtan(3)

NAME
       fixtan - Fixed point tangent of binary angles. Allegro game programming
       library.

SYNOPSIS
       #include <allegro.h>

       fixed fixtan(fixed x);

DESCRIPTION
       This function finds the tangent of a value using a lookup table. The
       input value must be a fixed point binary angle. Example:

          fixed angle, res_a, res_b;
          float dif;

          angle = itofix(37);
          /* Prove that tan(angle) == sin(angle) / cos(angle). */
          res_a = fixdiv(fixsin(angle), fixcos(angle));
          res_b = fixtan(angle);
          dif = fixtof(fixsub(res_a, res_b));
          allegro_message("Precision error: %f\n", dif);

RETURN VALUE
       Returns the tangent of a fixed point binary format angle. The return
       value will be in radians.

SEE ALSO

Allegro                          version 4.4.2                       fixtan(3)