Question

帮助？我不知道为什么会收到此错误。我在第39行：

term[1] = differentiate(Coeff[1], exponent[1]);

如何解决此问题？

完整代码列表：

public class Calcprog {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int numTerms = 7;
        double[] Coeff = new double[6];
        double[] exponent = new double[6];
        String[] term = new String[6];

        System.out.println("Enter the number of terms in your polynomial:");
        numTerms = input.nextInt();

        while (numTerms > 6) {
            if (numTerms > 6) {
                System.out.println("Please limit the number of terms to six.");
                System.out.println("Enter the number of terms in your polynomial:");
                numTerms = input.nextInt();
            }
        }

        for (int i = 1; i < numTerms + 1; i++) {
            System.out.println("Please enter the coefficient of term #" + i + " in decimal form:");
            Coeff[i] = input.nextDouble();
            System.out.println("Please enter the exponent of term #" + i + " in decimal form:");
            exponent[i] = input.nextDouble();
        }
        term[1] = differentiate(Coeff[1], exponent[1]);
    }

    public String differentiate(int co, int exp) {
        double newco, newexp;
        String derivative;
        newexp = exp - 1;
        newco = co * exp;
        derivative = Double.toString(newco) + "x" + Double.toString(newexp);
        return derivative;
    }
}

Answer 1

您正在尝试将双参数传递给接受整数的方法，这需要一个可能导致信息丢失的强制转换。

你可以通过一个明确的演员来使它工作：

term[1] = differentiate((int)Coeff[1], (int)exponent[1]);

或者您可以更改differentiate方法以接受双重参数，这可能更有意义：

public String differentiate(double co, double exp)

Answer 2

你的方法不是静态的，你在main中调用是静态的，记住一个非静态方法可以直接在静态方法中访问，你必须创建一个类的实例来访问该方法，还有您传递的参数是double而不是int。您的方法应该与public static String differentiate(double co, double exp){

类似

Answer 3

将Differeate方法的参数类型更改为double。这应该如下所示

  public String differentiate(double co, double exp){
    ...
  }

不兼容的类型：可能从double转换为int的有损转换

3 个答案: