EXP(3M)              INTERACTIVE UNIX System              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
               The exp function 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).

          DIAGNOSTICS
               The exp function 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


          Rev. C Software Development Set                            Page 1

          EXP(3M)              INTERACTIVE UNIX System              EXP(3M)



               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).














































          Rev. C Software Development Set                            Page 2