# isnormal() in C++

This function is defined in <cmath.h> . By using isnormal() function, we determines that whether the given number is normal (neither zero, infinite nor NAN) or not. This function returns 1 if the number is normal else return zero.

Syntax:

`bool  isnormal(float x);`

or

`bool  isnormal(double x); `

or

`bool  isnormal(long double x); `

Parameters: This functions takes a mandatory parameter x which represents the floating point value.

Returns: If the given value is normal then the function returns 1 otherwise the function returns zero.

Below program illustrate the isnormal() function in C++:

Example 1:- To show with float value

 `// c++ program to demonstrate ` `// example of isnormal() function. ` ` `  `#include ` ` `  `using` `namespace` `std; ` ` `  `int` `main() ` `{ ` ` `  `    ``float` `f = 7.0F; ` ` `  `    ``// check for non-zero value ` `    ``cout << ``"isnormal(7.0) is = "` `<< isnormal(f) << endl; ` ` `  `    ``// check for zero ` `    ``f = 0.0F; ` `    ``cout << ``"isnormal(0.0) is = "` `<< isnormal(f) << endl; ` ` `  `    ``// check for infinite value ` `    ``f = 9.2F; ` `    ``cout << ``"isnormal(9.2/0.0) is = "` `<< isnormal(f / 0.0) << endl; ` ` `  `    ``return` `0; ` `} `

Output:

```isnormal(7.0) is = 1
isnormal(0.0) is = 0
isnormal(9.2/0.0) is = 0
```

Example 2:- To show with double value

 `// c++ program to demonstrate ` `// example of isnormal() function. ` ` `  `#include ` ` `  `using` `namespace` `std; ` ` `  `int` `main() ` `{ ` ` `  `    ``double` `f = 7.0; ` ` `  `    ``// check for non-zero value ` `    ``cout << ``"isnormal(7.0) is = "` `<< isnormal(f) << endl; ` ` `  `    ``// check for zero ` `    ``f = 0.0; ` `    ``cout << ``"isnormal(0.0) is = "` `<< isnormal(f) << endl; ` ` `  `    ``// check for infinite value ` `    ``f = 9.2; ` `    ``cout << ``"isnormal(9.2/0.0) is = "` `<< isnormal(f / 0.0) << endl; ` ` `  `    ``return` `0; ` `} `

Output:

```isnormal(7.0) is = 1
isnormal(0.0) is = 0
isnormal(9.2/0.0) is = 0
```

Example 3:- To show with long double value

 `// c++ program to demonstrate ` `// example of isnormal() function. ` ` `  `#include ` ` `  `using` `namespace` `std; ` ` `  `int` `main() ` `{ ` ` `  `    ``long` `double` `f = 7.0; ` ` `  `    ``// check for non-zero value ` `    ``cout << ``"isnormal(7.0) is = "` `<< isnormal(f) << endl; ` ` `  `    ``// check for zero ` `    ``f = 0.0; ` `    ``cout << ``"isnormal(0.0) is = "` `<< isnormal(f) << endl; ` ` `  `    ``// check for infinite value ` `    ``f = 9.2; ` `    ``cout << ``"isnormal(9.2/0.0) is = "` `<< isnormal(f / 0.0) << endl; ` ` `  `    ``return` `0; ` `} `

Output:

```isnormal(7.0) is = 1
isnormal(0.0) is = 0
isnormal(9.2/0.0) is = 0
```

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