當前位置: 首頁>>編程示例 >>用法及示例精選 >>正文


C/C++ asin()、atan()用法及代碼示例


在C++中,asin()和atan()是用於數學計算的預定義函數。 math.h是各種數學函數所需的頭文件。該庫中所有可用的函數都將double作為參數,並返回double作為結果。

asin()

asin()函數用於查找數字的反正弦值,表示對該函數賦予正弦值,它將以弧度返回對應於該值的角度。在三角學中,反正弦是正弦的逆運算。
注意:傳遞給此函數的參數必須在[-1,1]之間。


用法:

double asin(double k)

參數:
k is the value whose corresponding angle we have to find.
// CPP code to illustrate 
// the use of asin function 
#include <bits/stdc++.h> 
using namespace std; 
  
#define PI 3.14159265 
  
int main() 
{ 
    double k, ret, val; 
  
    // Take any value between [-1, 1] 
    k = 0.5; 
    ret = asin(k); 
    val = (ret * 180) / PI; 
    cout << "The arcsine of " << k 
         << " is " << ret << " radians and "
         << val << " degrees"; 
  
    return 0; 
}

輸出:

The arcsine of 0.5 is 0.523599 radians and 30 degrees

atan()

atan()函數用於查找數字的反正切,表示對該函數給出正切值,它將以弧度返回對應於該值的角度。反正切是切線的逆運算。此函數接受所有實數。

用法:

double atan(double k)

參數:
k is the value whose corresponding angle we have to find.
// CPP code to illustrate 
// the use of atan function 
#include <bits/stdc++.h> 
using namespace std; 
  
#define PI 3.14159265 
  
int main() 
{ 
    double k, ret, val; 
  
    // Take any value 
    k = 1.0; 
    ret = atan(k); 
    val = (ret * 180) / PI; 
    cout << "The arctangent of " << k 
         << " is " << ret << " radians and "
         << val << " degrees"; 
  
    return 0; 
}

輸出:

The arctangent of 1 is 0.785398 radians and 45 degrees


相關用法


注:本文由純淨天空篩選整理自AKASH GUPTA 6大神的英文原創作品 asin() and atan() functions in C/C++ with Example。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。