c++中atan2函數
C ++ atan2()函數 (C++ atan2() function)
atan2() function is a library function of cmath header, it is used to find the principal value of the arc tangent of y/x, where y is the proportion of the y-coordinate and x is the proportion of the x-coordinate , it accepts two arguments (y, x) and returns arc tangent of y/x in radians.
atan2()函數是cmath標頭的庫函數，用于查找y / x的反正切的主值，其中y是y坐標的比例， x是x坐標的比例，它接受兩個參數(y，x)并以弧度返回y / x的反正切。
Syntax of atan2() function:
atan2()函數的語法：
atan2(y, x);
Parameter(s): y, x – are the numbers (proportions of y-coordinate and x-coordinate) to calculate the principal value of the arc tangent of y/x.
參數： y，x –是數字( y坐標和x坐標的比例)，用于計算y / x的反正切的主值。
Return value: double – it returns double type value that is the principal value of the arc tangent of y/x.
返回值： double-返回double類型的值，它是y / x的反正切的主要值。
Example:
例：
Input:
float x = -1.0;
float y = -2.5;
Function call:
atan2(y, x);
Output:
-1.9513
C ++代碼演示atan2()函數的示例 (C++ code to demonstrate the example of atan2() function)
// C++ code to demonstrate the example of
// atan2() function
#include <iostream>
#include <cmath>
using namespace std;
// main() section
int main()
{
float x;
float y;
x = -1.0;
y = -2.5;
cout<<"atan2("<<y<<","<<x<<"): "<<atan2(y,x)<<endl;
x = 11.0;
y = 22.5;
cout<<"atan2("<<y<<","<<x<<"): "<<atan2(y,x)<<endl;
x = -1.0;
y = 0;
cout<<"atan2("<<y<<","<<x<<"): "<<atan2(y,x)<<endl;
return 0;
}
Output
輸出量
atan2(-2.5,-1): -1.9513
atan2(22.5,11): 1.11608
atan2(0,-1): 3.14159
Reference: C++ atan2() function
參考： C ++ atan2()函數
翻譯自: https://www.includehelp.com/cpp-tutorial/atan2-function-with-example.aspx
c++中atan2函數
