cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ] #include <mathcw.h> extern float atanpif (float x); extern double atanpi (double x); extern long double atanpil (long double x); extern __float80 atanpiw (__float80 x); extern __float128 atanpiq (__float128 x); extern long_long_double atanpill (long_long_double x); extern decimal_float atanpidf (decimal_float x); extern decimal_double atanpid (decimal_double x); extern decimal_long_double atanpidl (decimal_long_double x); extern decimal_long_long_double atanpidll (decimal_long_long_double x);
NB: Functions with prototypes containing underscores in type names may be available only with certain extended compilers.
The inverse function tanpi(x) = tan(pi * x), avoid range-reduction issues because the argument x is always an exact scaling of pi.
The value of x should be in the range [-Infinity,+Infinity].