exp(3) - NetBSD Manual Pages

EXP(3)                  NetBSD Library Functions Manual                 EXP(3)


NAME

     exp, expf, exp2, exp2f, expm1, expm1f -- exponential functions


LIBRARY

     Math Library (libm, -lm)


SYNOPSIS

     #include <math.h>

     double
     exp(double x);

     float
     expf(float x);

     double
     exp2(double x);

     float
     exp2f(float x);

     double
     expm1(double x);

     float
     expm1f(float x);


DESCRIPTION

     The exp() and expf() functions compute the base e exponential value of
     the given argument x.

     The exp2() and exp2f() functions compute the base 2 exponential of the
     given argument x.

     The expm1() and expm1f() functions compute the value exp(x)-1 accurately
     even for tiny argument x.


RETURN VALUES

     These functions will return the appropriate computation unless an error
     occurs or an argument is out of range.  The functions exp() and expm1()
     detect if the computed value will overflow, set the global variable errno
     to ERANGE and cause a reserved operand fault on a VAX.


SEE ALSO

     math(3)


STANDARDS

     The exp() function conforms to ANSI X3.159-1989 (``ANSI C89'').  The
     exp2(), exp2f(), expf(), expm1(), and expm1f() functions conform to
     ISO/IEC 9899:1999 (``ISO C99'').


HISTORY

     The exp() functions appeared in Version 1 AT&T UNIX.  The expm1() func-
     tion appeared in 4.3BSD.

NetBSD 9.3                     September 2, 2019                    NetBSD 9.3