exp(3M)                  UNIX System V(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)                  UNIX System V(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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