C++ atanh()用法及代码示例

atanh()是C++ STL中的内置函数，该函数返回以弧度给出的角度的反双曲正切值。

用法:

atanh(data_type x)

参数：该函数接受一个强制性参数x，该参数指定弧度的反双曲角在[-1，1]范围内。该参数可以是double，float或long double数据类型。

返回值：此函数以弧度形式返回参数的反双曲正弦值，具体取决于在参数中传递的参数。下表中给出了不同的返回值：

以下示例程序旨在说明上述方法：

示例1:

// C++ program to illustrate 
// the atanh() function 
// all return values 
#include <bits/stdc++.h> 
using namespace std; 
  
int main() 
{ 
    // Return value when -1<x<1 
    int x = 0; 
    // Function call to calculate atanh(x) value 
    double result = atanh(x); 
  
    cout << "atanh(0) = " << result << " radians\n"; 
    cout << "atanh(0) = " << result * 180 / 3.141592 
         << " degrees\n"; 
  
    // Return value when x=-1 
    x = -1; 
    result = atanh(x); 
  
    cout << "\natanh(-1) = " << result << " radians\n"; 
    cout << "atanh(-1) = " << result * 180 / 3.141592 
         << " degrees\n"; 
  
    // Return value when x=1 
    x = 1; 
    result = atanh(x); 
  
    cout << "\natanh(1) = " << result << " radians\n"; 
    cout << "atanh(1) = " << result * 180 / 3.141592 
         << " degrees\n"; 
  
    // Return value when x<-1 or x>1 
    x = -2; 
    result = atanh(x); 
  
    cout << "\natanh(-2) = " << result << " radians\n"; 
    cout << "atanh(-2) = " << result * 180 / 3.141592 
         << " degrees\n"; 
  
    return 0; 
}

输出：

atanh(0) = 0 radians
atanh(0) = 0 degrees

atanh(-1) = -inf radians
atanh(-1) = -inf degrees

atanh(1) = inf radians
atanh(1) = inf degrees

atanh(-2) = -nan radians
atanh(-2) = -nan degrees

错误和异常：当传递字符串或任何其他data_type以外的函数时，该函数将返回不匹配的函数错误消息。

示例2:

// C++ program to demonstrate 
// the atanh() function  
// string passed 
#include <bits/stdc++.h> 
using namespace std; 
  
int main() 
{ 
    string x = "gfg"; 
  
    // Function call to calculate atanh(x) value 
    double result = atanh(x); 
  
    cout << "atanh(50.0) = " << result << " radians" << endl; 
    cout << "atanh(50.0) = " << result * 180 / 3.141592 
         << " degrees" << endl; 
    return 0; 
}

输出：

prog.cpp:11:25: error: no matching function for call to 'atanh(std::__cxx11::string&)'
  double result = atanh(x);

相关用法

注：本文由纯净天空筛选整理自pawan_asipu大神的英文原创作品 atanh() function in C++ STL。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。