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scalbn
, scalbnf
, scalbln
, scalblnf
—scale by power of FLT_RADIX (=2)Synopsis
#include <math.h> double scalbn(double x, int n); float scalbnf(float x, int n); double scalbln(double x, long int n); float scalblnf(float x, long int n);
Description
The scalbn
and scalbln
functions compute
x times FLT_RADIX to the power n.
efficiently. The result is computed by manipulating the exponent, rather than
by actually performing an exponentiation or multiplication. In this
floating-point implementation FLT_RADIX=2, which makes the scalbn
functions equivalent to the ldexp
functions.
Returns
x times 2 to the power n. A range error may occur.
Portability
ANSI C, POSIX
See Also
ldexp