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exp(3)                   BSD Library Functions Manual                   exp(3)


NAME

     exp, exp2, expm1 -- exponential functions


SYNOPSIS

     #include <math.h>

     double
     exp(double x);

     long double
     expl(long double x);

     float
     expf(float x);

     double
     exp2(double x);

     long double
     exp2l(long double x);

     float
     exp2f(float x);

     double
     expm1(double x);

     long double
     expm1l(long double x);

     float
     expm1f(float x);


DESCRIPTION

     The exp() function computes e**x, the base-e exponential of x.

     The exp2() function computes 2**x, the base-2 exponential of x.

     The expm1() function computes the base-e exponential of x , minus 1 accu-
     rately even for very small values of x.


SPECIAL VALUES

     exp(+-0) and exp2(+-0) return 1.

     exp(-infinity) and exp2(-infinity) return +0.

     exp(+infinity) and exp2(+infinity) return +infinity.

     expm1(+-0) returns +-0.

     expm1(-infinity) returns -1.

     expm1(+infinity) returns +infinity.

     For all these functions, a range error occurs if the magnitude of x is
     too large.


SEE ALSO

     math(3)


STANDARDS

     The exp() , exp2() , and expm1() functions conform to ISO/IEC
     9899:1999(E).

4th Berkeley Distribution      December 11, 2006     4th Berkeley Distribution

Mac OS X 10.6 - Generated Thu Sep 17 20:19:40 CDT 2009