如何在一個方法中使用另一種方法中的變量？

Question

因此，我正在爲這所學校做這個項目，我覺得這很簡單，但我真的很愚蠢。我需要兩種方法;一個只做我想做的計算，另一個用戶輸入數字並顯示計算方法的答案。來自班級網站的樣本可以輕鬆理解如何使用一個用戶輸入的變量，但不是像我需要的那樣;我還需要能夠將它們全部放在一起並在方程中使用它們。這是我到目前爲止：

import java.util.*; 
import java.text.*; 

public class Lab3StarterCodeExperimental { 
    public static final Scanner CONSOLE = new Scanner(System.in); 

    public static double compoundInterest(double accountValue) { 
    double firstCalc = accountValue * 150; 
    return firstCalc; 
    } 


    public static void main(String [] args) { 
    //print title of lab 
    System.out.println("Lab 3"); 

    //get user input (present value of account, interest rate, # years, payment per year) 
    System.out.print("Enter present value of the account: "); 
    double presentValue = CONSOLE.nextDouble(); 
    System.out.print("Enter the interest rate of the account: "); 
    double interestRate = CONSOLE.nextDouble(); 
    System.out.print("Enter the number of years: "); 
    double numOfYears = CONSOLE.nextDouble(); 

    //calculate future value of account 
    double fvAccount = compoundInterest(presentValue); 

    //calculate future value of annuity 

    //print everything 
    System.out.println("Fake Variable is " + presentValue); 
    System.out.println("Future value of account is " + fvAccount); 
    } 
} 

任何幫助非常感謝！

Answer 1

public double getWhateverResult(double presentValue, double interestRate, double numOfYears) { 
    double doubleResult = //do stuff 
    return doubleResult; 
} 

與

double doubleResult = getWhateverResult(presentValue, interestRate, numOfYears); 
System.out.println(doubleResult);