C++ Usage and example of scalbn() function

C++ Library Function <cmath>

C ++The scalbn() function in takes two parameters: x and n, which calculates the product of x and FLT_RADX multiplied by n.

In simple terms, the scalbn() function returns the product of x and FLT_RADIX raised to the power of n.

FLT_RADIX is the value of the base (integer base) in the exponential form of the exponent.

The function is in<cmath>Defined in the header file. In addition, you need to use the <cfloat> header file to use FLT_RADIX.

scalbn(x, n) = x　*　FLT_RADIXn

scalbn() prototype [from C ++ 11Standard library begins]

double scalbn (double x, int n);
float scalbn (float x, int n);
long double scalbn (long double x, int n);
double scalbn (T x, int n);　//Here, T is an integer type

It is similar toscalbln() functionare the same, but it takes int as the second parameter.

scalbn() parameters

scalbn() accepts two parameters:

• x -The value representing the number of significant digits.

• n-The exponent value of FLT_RADIX.

The return value of scalbn()

The scalbn() function returns. x * FLT_RADIXⁿ

If the result is too large to be represented by the return type's value, the function returns HUGE_VAL with the correct sign.

Example: How does scalbn() work?

#include <iostream>
#include <cmath>
#include <cfloat>
using namespace std;
int main()}
{
	int n =　13;
	double x =　3.056, result;
	result = scalbn(x, n);
	cout << x << "　*　" << FLT_RADIX << "^" << n << " = " << result << endl;
	return 0;
}

When the program is run, the output is:

3.056　*　2^13　=　25034.8

　 C++ Library Function <cmath>