# scalbn() function in C++

The scalbn() function is defined in the cmath header file. This function is used to calculate the product of given number x and FLT_RADIX raised to the power n.

Syntax:-

`float scalbn(float x, int n); `

or

`double scalbn(double x, int n); `

or

`long double scalbn(long double x, int n); `

or

`double scalbn(integral x, int n);  `

Parameters:- This method takes two parameters:

• x: This represents the value of significand.
• n: This represents the value of the exponent.

Return Value: This function returns the product of given number x and FLT_RADIX raised to the power n. with the help of formula:

`scalbn(x, n) = x * FLT_RADIXn`

Below programs illustrate the above function:-

Example 1:-

 `// C++ program to demonstrate ` `// example of scalbn() function. ` ` `  `#include ` `using` `namespace` `std; ` ` `  `int` `main() ` `{ ` `    ``int` `n = 7; ` `    ``int` `x = 5; ` `    ``int` `ans; ` ` `  `    ``ans = scalbn(x, n); ` `    ``cout << x << ``" * "` `         ``<< FLT_RADIX << ``"^"` `         ``<< n << ``" = "` `         ``<< ans << endl; ` ` `  `    ``return` `0; ` `} `

Output:

```5 * 2^7 = 640
```

Example 2:-

 `// C++ program to demonstrate ` `// example of scalbn() function. ` ` `  `#include ` `using` `namespace` `std; ` ` `  `int` `main() ` `{ ` `    ``int` `n = 7; ` `    ``double` `x = 3.9; ` `    ``int` `ans; ` ` `  `    ``ans = scalbn(x, n); ` `    ``cout << x << ``" * "` `         ``<< FLT_RADIX << ``"^"` `         ``<< n << ``" = "` `         ``<< ans << endl; ` ` `  `    ``return` `0; ` `} `

Output:

```3.9 * 2^7 = 499
```

## tags:

C++ CPP-Functions CPP-Library CPP