Thread: Need help with user imput

Im trying to make a program that does a formula and the user imputs the variables and it prints the result.
I dont know terminology, so im just gona call this the class with the formula

//Geometeric Series - Sn = (1-r^(n-1))/(1-r) 
 
 
 
public class geometricSeries 
{ 
public static double geometricSeries(double a, int n, double r)
{
 
double sum = (1-(Math.pow(r,n)))/(1-r);
return sum;  
}
}

This is the user imput part i have a problem with

import java.util.Scanner;
 
public class geometricSeriesDriver
{
 public static void main(String[]args);
 {
  System.out.println("Imput the first term");
 
  Scanner scan = new Scanner(System.in);
  double a = scan.nextDouble;
 
  System.out.println("Imput the n term");
  int n = scan.nextInt;
 
  System.out.prinln("Imput the ratio");
  double r = scan.nextDouble;
 
  return sum; 
  }
 }

I have no idea how to connect the two, its been like 2 weeks since ive written code and im just starting so i kind of forgot how. Also i get these errors.
geometricSeriesDriver.java:5: error: missing method body, or declare abstract
public static void main(String[]args);
^
geometricSeriesDriver.java:10: error: cannot find symbol
double a = scan.nextDouble;
^
symbol: variable nextDouble
location: variable scan of type Scanner
geometricSeriesDriver.java:13: error: cannot find symbol
int n = scan.nextInt;
^
symbol: variable nextInt
location: variable scan of type Scanner
geometricSeriesDriver.java:15: error: cannot find symbol
System.out.prinln("Imput the ratio");
^
symbol: method prinln(String)
location: variable out of type PrintStream
geometricSeriesDriver.java:16: error: cannot find symbol
double r = scan.nextDouble;
^
symbol: variable nextDouble
location: variable scan of type Scanner
geometricSeriesDriver.java:18: error: return outside method
return sum;
^
6 errors

errors could be fixed by changing scan.nextDouble; to scan.nextDouble(); and scan.nextInt; to scan.nextInt();

There is no method of prinln(), I think it should be println();

Why not just move the method into the geometricSeriesDriver class?

Like so;

public class geometricSeriesDriver
{
 
  public static double geometricSeries(double a, int n, double r)
  {
 
    double sum = (1-(Math.pow(r,n)))/(1-r);
    return sum;  
  }
 
  public static void main(String[]args);
  {
    System.out.println("Imput the first term");
 
    Scanner scan = new Scanner(System.in);
    double a = scan.nextDouble;
 
    System.out.println("Imput the n term");
    int n = scan.nextInt;
 
    System.out.prinln("Imput the ratio");
    double r = scan.nextDouble;
 
    return sum; 
   }
 }

As the other user mentioned, you need add a () to nextInt and nextDouble to become nextInt() nextDouble()

also you never defined the variable sum. so it would be: double sum;

do you know how to call a method?

Originally Posted by copeg

Please read the compile messages posted in post #3 above - your code just recapitulates the errors.

I just want to know why he/she has a separate class when you could put the whole thing in just one class. I wasnt trying to debug those errors; though i have fixed the code and runs on my machine lol.

I want to see if the OP has figured it out