java - 可能是类型转换问题 - Java

Question

我写了下面的代码:

public class Point2
{
    private double _radius , _alpha;    

    public Point2 ( int x , int y )
    {
        //if one or more of the point values is <0 , the constructor will state a zero value.
        if (x < 0)  
        {
           x = 0;
        }

        if (y < 0)
        {
           y = 0;
        }
        _radius = Math.sqrt ( Math.pow(x,2) + Math.pow (y,2) ) ;
        _alpha = Math.toDegrees( Math.atan ((double)y/x) );
    }

    public Point2 (Point2 other) // copy constructor
    {
        this._radius = other._radius ;
        this._alpha = other._alpha ;
    }

    public int getX()
    {
       return (int) Math.round ( Math.sin(_alpha)*_radius );
    }

    public int getY()
    {
        return (int) Math.round ( Math.cos(_alpha)*_radius );   
    }

    public void setX (int x)
    {
        if (x >=0 )
        {
            _radius = Math.sqrt ( Math.pow (x,2) + Math.pow(getY(),2) );
            _alpha = Math.toDegree ( Math.atan ((double)getY()/x));
        } 
    }
}

问题是编译器给我一个错误:_alpha = Math.toDegrees( Math.atan ((double)y/x) ); 它说:“*找不到符号 - 方法 toDegree(double) ; 也许你的意思是:toDegrees(double)* "

似乎是什么问题？

谢谢!

Answer 1

阅读您的代码!

    _radius = Math.sqrt ( Math.pow (x,2) + Math.pow(getY(),2) );
    _alpha = Math.toDegree ( Math.atan ((double)getY()/x));

那一行写的是 Math.toDegree 而不是 toDegrees!