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       exp, expf, expl - base-e exponential function


       #include <math.h>

       double exp(double x);
       float expf(float x);
       long double expl(long double x);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       expf(), expl(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
       _ISOC99_SOURCE; or cc -std=c99


       The exp() function  returns  the  value  of  e  (the  base  of  natural
       logarithms) raised to the power of x.


       On success, these functions return the exponential value of x.

       If x is a NaN, a NaN is returned.

       If x is positive infinity, positive infinity is returned.

       If x is negative infinity, +0 is returned.

       If the result underflows, a range error occurs, and zero is returned.

       If the result overflows, a range error occurs, and the functions return
       +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL, respectively.


       See math_error(7) for information on how to determine whether an  error
       has occurred when calling these functions.

       The following errors can occur:

       Range error, overflow
              errno  is  set  to ERANGE.  An overflow floating-point exception
              (FE_OVERFLOW) is raised.

       Range error, underflow
              errno is set to ERANGE.  An underflow  floating-point  exception
              (FE_UNDERFLOW) is raised.


       C99, POSIX.1-2001.  The variant returning double also conforms to SVr4,
       4.3BSD, C89.


       cbrt(3), cexp(3), exp10(3), exp2(3), sqrt(3)


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                                  2008-08-05                            EXP(3)