scalbln

scalbln

Scale a floating point number

Portability: C99

SYNOPSIS
DESCRIPTION
RETURN VALUE
IMPLEMENTATION
USAGE NOTES
RELATED FUNCTIONS
SEE ALSO

SYNOPSIS

   #include <math.h>

   double scalbln(double x, long n);
   float scalblnf(float x, long n);
   long double scalblnl(long double x, long n);

DESCRIPTION

scalbln is used to scale a floating-point number by a power of the floating-point base (16 for hexadecimal floating point, 2 for binary floating point). The result is:

[IMAGE]

where b is the floating-point base.

The function name scalblnf should be used for float arguments, and scalblnl for long double arguments. Alternately, if the header file tgmath.h is included, scalbln may be used with any numeric argument type.

RETURN VALUE

scalbln returns the argument, x, scaled by the floating-point base raised to the power n, if that value is expressible.

IMPLEMENTATION

For binary floating-point, scalbln is implemented as a built-in function unless it is undefined by a #undef statement.

USAGE NOTES

scalbln resembles the scalbn function, but differs in using the type long for the exponent.

RELATED FUNCTIONS

ilogb, ldexp, logb, scalbn

SEE ALSO

"Mathematical Functions" in Chapter 2, "Function Categories"

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