NAME

exp - exponential function

 SYNOPSIS

#include <math.h>

double exp(double x);

 DESCRIPTION

The exp() function computes the exponent of x, defined as e^x.

An application wishing to check for error situations should set errno to 0 before calling exp(). If errno is non-zero on return, or the return value is NaN, an error has occurred.

 RETURN VALUE

Upon successful completion, exp() returns the exponential value of x.

If the correct value would cause overflow, exp() returns HUGE_VAL and sets errno to [ERANGE].

If the correct value would cause underflow, exp() returns 0 and may set errno to [ERANGE].

If x is NaN, NaN is returned and errno may be set to [EDOM].

 ERRORS

The exp() function will fail if:

[ERANGE]

The result overflows.

The exp() function may fail if:

[EDOM]

The value of x is NaN.

[ERANGE]

The result underflows.

No other errors will occur.

 EXAMPLES

None.

 APPLICATION USAGE

None.

 FUTURE DIRECTIONS

None.

 SEE ALSO

isnan(), log(), <math.h>.

DERIVATION

Derived from Issue 1 of the SVID.