◄Description► ◄Example► ◄Up► ◄Contents► ◄Index► ◄Back► ─────Run-Time Library─────────────────────────────────────────────────────── Include: <math.h>, <errno.h> Syntax: double log( double x ); double log10( double x ); long double _logl( long double x ); long double _log10l( long double x ); Returns: the logarithm of <x> if successful; -HUGE_VAL (or -_LHUGE_VAL for the long double functions) if not. errno: EDOM (if <x> is less than 0) ERANGE (if <x> is equal to 0) See also: exp, ldexp, frexp, pow, sqrt, _matherr -♦-