What is scalbnl in C/C++?

We use the scalbnl() function to compute the product of a given number with FLT_RADIX raised to the given power. It is a variation of the scalbn() function when the mantissa value is of type long double.

FLT_RADIX is a constant which serves as the base of the exponent. Usually, in all computers, this value is 2.

Library For C++

#include<cmath>

Library For C

#include<math.h>

We have to use #include<cfloat> library for C++ and #include<float.h> library for C language to access FLT_RADIX .

Syntax

long double scalbnl(long double num, int n)

Parameters

num: Input value is of long double type. This is the coefficient or mantissa value.

n: Exponent value or the number to which FLT_RADIX is raised.

Return value

The return value is the product of the given number, num, with FLT_RADIX raised to power n.

Formula

widget

Code

#include <iostream>
#include<cmath>
#include <cfloat>
using namespace std;
int main()
{
  long double num = 100.9;
  int n = 4;
  long double result = 0;
  cout << num << " * " << FLT_RADIX << "^" << n << " = " << scalbnl(num , n) << endl;
}

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