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EXP(3)                     Library Functions Manual                     EXP(3)

NAME
     exp, expf, expl, exp2, exp2f, exp2l, expm1, expm1f expm1l - exponential
     functions

LIBRARY
     Math Library (libm, -lm)

SYNOPSIS
     #include <math.h>

     double
     exp(double x);

     float
     expf(float x);

     long double
     expf(long double x);

     double
     exp2(double x);

     float
     exp2f(float x);

     long double
     exp2l(long double x);

     double
     expm1(double x);

     float
     expm1f(float x);

     long double
     expm1l(long double x);

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

     The exp2(), exp2f(), and exp2l() functions compute the base 2 exponential
     of the given argument x.

     The expm1(), expm1f() and expm1l() 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(), exp2l(), expf(), expl(), expm1(), expm1f(), and expm1l()
     functions conform to ISO/IEC 9899:1999 ("ISO C99").

HISTORY
     The exp() functions appeared in Version 1 AT&T UNIX.  The expm1()
     function appeared in 4.3BSD.

NetBSD 11.99                   January 24, 2024                   NetBSD 11.99