scalbln(), scalblnf(), scalblnl()

Load the exponent of a radix-independent floating point number

Synopsis:

#include <math.h>

double scalbln ( double x,
                 long int n );

float scalblnf ( float x,
                 long int n );

long double scalblnl ( long double x,
                       long int n );

Arguments:

x: The floating point number that you want to multiply by the exponent.
n: The exponent to apply to the radix of the machine's floating-point arithmetic.

Library:

libm

Use the -l m option to qcc to link against this library.

Description:

The scalbln(), scalblnf(), and scalblnl() functions compute x × rⁿ, where r is the radix of the machine's floating-point arithmetic. The difference between the scalbn* and scalbln* functions is the type of the second argument.

To check for error situations, use feclearexcept() and fetestexcept(). For example:

Call feclearexcept(FE_ALL_EXCEPT) before calling scalbln(), scalblnf(), or scalblnl().
On return, if fetestexcept(FE_ALL_EXCEPT) is nonzero, then an error has occurred.

Returns:

x × rⁿ

If:	These functions return:	Errors:
`x` is NaN	NaN	—
`x` is ±0.0 or ±Inf	`x`	—
`n` is 0	`x`	—
The correct value would cause underflow	The correct value, after rounding	FE_UNDERFLOW
The correct value would cause overflow	Inf	FE_OVERFLOW

These functions raise FE_INEXACT if the FPU reports that the result can't be exactly represented as a floating-point number.

Classification:

ANSI, POSIX 1003.1

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	No
Thread	Yes