EXP(3M) (Math Libraries) EXP(3M)
NAME
exp, log, log10, pow, sqrt - exponential, logarithm, power,
square root functions
SYNOPSIS
#include <math.h>
double exp (x)
double x;
double log (x)
double x;
double log10 (x)
double x;
double pow (x, y)
double x, y;
double sqrt (x)
double x;
DESCRIPTION
exp returns ex.
Log returns the natural logarithm of x. The value of x must
be positive.
Log10 returns the logarithm base ten of x. The value of x
must be positive.
Pow returns xy. If x is zero, y must be positive. If x is
negative, y must be an integer.
Sqrt returns the non-negative square root of x. The value
of x may not be negative.
SEE ALSO
hypot(3M), matherr(3M), sinh(3M).
Page 1 May 1989
EXP(3M) (Math Libraries) EXP(3M)
DIAGNOSTICS
exp returns HUGE when the correct value would overflow, or 0
when the correct value would underflow, and sets errno to
ERANGE.
Log and log10 return -HUGE and set errno to EDOM when x is
non-positive. A message indicating DOMAIN error (or SING
error when x is 0) is printed on the standard error output.
Pow returns 0 and sets errno to EDOM when x is 0 and y is
non-positive, or when x is negative and y is not an integer.
In these cases a message indicating DOMAIN error is printed
on the standard error output. When the correct value for
pow would overflow or underflow, pow returns +HUGE or 0
respectively, and sets errno to ERANGE.
Sqrt returns 0 and sets errno to EDOM when x is negative. A
message indicating DOMAIN error is printed on the standard
error output.
These error-handling procedures may be changed with the
function matherr(3M).
Page 2 May 1989