NAME
exp2() — base-2 exponential function
SYNOPSIS
#include <math.h>
double exp2(double x);
DESCRIPTION
exp2()
returns
2x.
The ISO/ANSI C committee has approved the
exp2()
function for inclusion in the C9X draft standard.
To use this function, compile either with the default
-Ae
option or with the
-Aa
and
-D_HPUX_SOURCE
options. Make sure your program includes
<math.h>.
Link in the math library by specifying
-lm
on the compiler or linker command line.
RETURN VALUE
If
x
is +INFINITY,
exp2()
returns +INFINITY.
If
x
is -INFINITY,
exp2()
returns +zero.
If
x
is NaN,
exp2()
returns NaN.
If the correct value after rounding would be smaller in magnitude than
MINDOUBLE,
exp2()
returns zero.
If the magnitude of
x
is too large,
exp2()
returns
+INFINITY.
ERRORS
No errors are defined.
