| is_nan | Function (ROM Call 0x306)

AMS 1.01 or higher | math.h, timath.h

short is_nan (float x);

Checks whether the argument is Not_a_Number.

is_nan returns TRUE if x is NAN (Not_a_Number), else returns FALSE. Not_a_Number is a special value which is produced as a result of all operations when the result is undefined or non-real, for example dividing zero with zero, calculating the logarithm of a negative number, etc.

Uses: _bcd_math
Used by: cacos, casin, cln, cosh, float_class, fmod, is_transfinite, itrig, sinh, tanh, did_push_anti_deriv, push_1st_derivative, push_abs, push_csolve, push_czeros, push_def_int, push_desolve, push_lim, push_max, push_min, push_nsolve, push_solve, push_zeros, did_push_to_polar, push_equals, push_exponentiate, push_greater_than, push_greater_than_or_equals, push_less_than, push_less_than_or_equals, push_not_equals, push_to_cylin, push_Float, did_push_approx_inflection_point, get_ub, GM_Intersect, GM_Math1, GT_Trace, Regraph, replace_top_with_post_simplified