java为二次方程式ax^2+bx+c=0设计一个类

public class QuadraticEquationtest //测试类
{
public static void main(String[] args)
{
//三个a，b，c
Quadraticequation equation1=new Quadraticequation(1.0,3,1);
Quadraticequation.ret(equation1);
Quadraticequation equation2=new Quadraticequation(1,2.0,1);
Quadraticequation.ret(equation2);
Quadraticequation equation3=new Quadraticequation(1,2,3);
Quadraticequation.ret(equation3);
}
}
class Quadraticequation
{
private double a;
private double b;
private double c;
public Quadraticequation(double x,double y,double z)//构造一个有参方法
{
a=x;
b=y;
c=z;
}
public double getA()
{
return a;
}
public double getB()
{
return b;
}
public double getC()
{
return c;
}
public double getDiscriminant()
{
return b*b-4*a*c;
}
public double getRoot1()
{
return (-b+Math.sqrt(getDiscriminant()))/(2*a);
}
public double getRoot2()
{
return (-b-Math.sqrt(getDiscriminant()))/(2*a);
}
public static void ret(Quadraticequation equation)//ret方法，防止代码过多
{
double ret1=equation.getDiscriminant();
if(ret1>0)
{
System.out.println("The equation has two roots "+equation.getRoot1()+" and "+equation.getRoot2());
}
else if(ret1==0)
{
System.out.println("The equation has one roots "+equation.getRoot1());
}
else
{
System.out.println("The equation has no real roots");
}
}
}

原文地址：https://blog.51cto.com/14233078/2389430