# libm.info: scalbn

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# `scalbn', `scalbnf'--scale by integer

*Synopsis*
#include <math.h>
double scalbn(double X, int Y);
float scalbnf(float X, int Y);
*Description*
`scalbn' and `scalbnf' scale X by N, returning X times 2 to the power
N. The result is computed by manipulating the exponent, rather than by
actually performing an exponentiation or multiplication.

*Returns*
X times 2 to the power N.

*Portability*
Neither `scalbn' nor `scalbnf' is required by ANSI C or by the System V
Interface Definition (Issue 2).

Created Mon Nov 8 17:42:56 2004 on tillpc with info_to_html version 0.9.6.