exp(3M)                      (Math Libraries)                       exp(3M)


   NAME
         exp, expf, cbrt, log, logf, log10, log10f, pow, powf, sqrt, sqrtf -
         exponential, logarithm, power, square root functions

   SYNOPSIS
         cc [flag ...] file ...  -lm [library ...]

         cc -O -Ksd [flag ...] file ...  -J sfm [library ...]

         #include <math.h>

         double exp (double x);

         float expf (float x);

         double cbrt (double x);

         double log (double x);

         float logf (float x);

         double log10 (double x);

         float log10f (float x);

         double pow (double x, double y);

         float powf (float x, float y);

         double sqrt (double x);

         float sqrtf (float x);

   DESCRIPTION
         exp and expf return ex.

         cbrt returns the cube root of x.

         log and logf return the natural logarithm of x.  The value of x must
         be positive.

         log10 and log10f return the base ten logarithm of x.  The value of x
         must be positive.

         pow and powf return xy.  If x is 0, y must be positive.  If x is
         negative, y must be an integer.

         sqrt and sqrtf return the non-negative square root of x.  The value
         of x may not be negative.




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   exp(3M)                      (Math Libraries)                       exp(3M)


   SEE ALSO
         hypot(3M), matherr(3M), sinh(3M).

   DIAGNOSTICS
         exp and expf return HUGE when the correct value would overflow, or 0
         when the correct value would underflow, and set errno to ERANGE.

         log, logf, log10, and log10f return -HUGE and set errno to EDOM when
         x is non-positive.  A message indicating DOMAIN error is printed on
         standard error.

         pow and powf return 0 and set 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 standard
         error.  When the correct value for pow or powf would overflow or
         underflow, these functions return +HUGE or 0, respectively, and set
         errno to ERANGE.

         sqrt and sqrtf return 0 and set errno to EDOM when x is negative.  A
         message indicating DOMAIN error is printed on standard error.

         Except when the -Xc compilation option is used, these error-handling
         procedures may be changed with the function matherr.  When the -Xa or
         -Xc compilation options are used, HUGEVAL is returned instead of
         HUGE and no error messages are printed.  In these compilation modes,
         pow and powf return 1, with no error, when both x and y are 0; when x
         is 0 and y is negative, they return -HUGEVAL and set errno to EDOM.
         Under -Xc, log and logf return -HUGEVAL and set errno to ERANGE when
         x is 0.  Under -Xc, sqrt and sqrtf return NaN when x is negative.
























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