C++ isnormal()用法及代碼示例

此函數在中定義。通過使用isnormal()函數，我們確定給定的數字是否正常(既不是零，無窮也不是NAN)。如果數字正常，則此函數返回1，否則返回零。

用法:

bool  isnormal(float x);

或者

bool  isnormal(double x);

或者

bool  isnormal(long double x);

參數：該函數采用一個強製參數x，該參數表示浮點值。

返回：如果給定值正常，則函數返回1，否則函數返回零。

以下示例程序旨在說明C++中的isnormal()函數：

示例1：以浮點值顯示

// c++ program to demonstrate 
// example of isnormal() function. 
  
#include <bits/stdc++.h> 
  
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; 
}

輸出：

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

示例2：顯示雙倍價值

// c++ program to demonstrate 
// example of isnormal() function. 
  
#include <bits/stdc++.h> 
  
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; 
}

輸出：

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

示例3：顯示長雙值

// c++ program to demonstrate 
// example of isnormal() function. 
  
#include <bits/stdc++.h> 
  
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; 
}

輸出：

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

相關用法

C++ cin get()用法及代碼示例

注：本文由純淨天空篩選整理自bansal_rtk_大神的英文原創作品 isnormal() in C++。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。