개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(1M)을 검색하려면 섹션에서 1M 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

log(3m)

Mathematical Library Functions                                         log(3M)



NAME
       log, logf, logl - natural logarithm function

SYNOPSIS
       c99 [ flag... ] file... -lm [ library... ]
       #include <math.h>

       double log(double x);


       float logf(float x);


       long double logl(long double x);

DESCRIPTION
       These  functions  compute  the  natural  logarithm of their argument x,
       log(e)(x).

RETURN VALUES
       Upon successful completion, log() returns the natural logarithm of x.


       If x is ±0, a pole error occurs and log(), logf(),  and  logl()  return
       −HUGE_VAL, −HUGE_VALF, and −HUGE_VALL, respectively.


       For  finite values of x that are less than 0, or if x is −Inf, a domain
       error occurs and a NaN is returned.


       If x is NaN, a NaN is returned.


       If x is 1, +0 is returned.


       If x is +Inf, x is returned.


       For exceptional cases, matherr(3M) tabulates the values to be  returned
       by log() as specified by SVID3 and XPG3.

ERRORS
       These functions will fail if:

       Domain Error    The finite value of x is negative, or x is -Inf.

                       If   the   integer   expression   (math_errhandling   &
                       MATH_ERREXCEPT) is non-zero, the invalid floating-point
                       exception is raised.

                       The log() function sets errno to EDOM if the value of x
                       is negative.


       Pole Error      The value of x is 0.

                       If   the   integer   expression   (math_errhandling   &
                       MATH_ERREXCEPT)  is non-zero, the divide-by-zero float‐
                       ing-point exception is raised.


USAGE
       An application wanting to check for exceptions should  call  feclearex‐
       cept(FE_ALL_EXCEPT)  before  calling  these  functions.  On  return, if
       fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is
       non-zero,  an  exception  has been raised. An application should either
       examine the return value or check the floating point exception flags to
       detect exceptions.


       An application can also set errno to 0 before calling log(). On return,
       if errno is non-zero, an error has  occurred.  The  logf()  and  logl()
       functions do not set errno.

ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i)


       ATTRIBUTE  TYPEATTRIBUTE  VALUE _ Interface StabilityCommitted _ Avail‐
       abilitysystem/library/math  _  MT-LevelMT-Safe  _   StandardSee   stan‐
       dards(7).


SEE ALSO
       log10(3M), math.h(3HEAD), exp(3M), feclearexcept(3M), fetestexcept(3M),
       isnan(3M), log1p(3M), matherr(3M), attributes(7), standards(7)



Solaris 11.4                     27 Sept 2016                          log(3M)