Example usage for java.util Scanner nextDouble

Introduction

In this page you can find the example usage for java.util Scanner nextDouble.

Prototype

public double nextDouble() 

Source Link

Document

Scans the next token of the input as a double .

Usage

From source file:MainClass.java

public static void main(String args[]) {
    String instr = "10 99.88 scanning is easy.";
    Scanner conin = new Scanner(instr);

    while (conin.hasNext()) {
        if (conin.hasNextDouble()) {
            System.out.println(conin.nextDouble());
        }/*from  w ww  .  j a v  a  2s  .com*/
    }

}

---

From source file:MainClass.java

public static void main(String args[]) throws IOException {

    int count = 0;
    double sum = 0.0;

    FileWriter fout = new FileWriter("test.txt");
    fout.write("2 3.4 5 6 7.4 9.1 10.5 done");
    fout.close();/*  ww w  . j av  a 2 s . c o m*/

    FileReader fin = new FileReader("Test.txt");

    Scanner src = new Scanner(fin);

    while (src.hasNext()) {
        if (src.hasNextDouble()) {
            sum += src.nextDouble();
            count++;
        } else {
            String str = src.next();
            if (str.equals("done"))
                break;
            else {
                System.out.println("File format error.");
                return;
            }
        }
    }

    fin.close();
    System.out.println("Average is " + sum / count);
}

---

From source file:Retirement.java

public static void main(String[] args) {
    // read inputs
    Scanner in = new Scanner(System.in);

    System.out.print("How much money do you need to retire? ");
    double goal = in.nextDouble();

    System.out.print("How much money will you contribute every year? ");
    double payment = in.nextDouble();

    System.out.print("Interest rate in %: ");
    double interestRate = in.nextDouble();

    double balance = 0;
    int years = 0;

    // update account balance while goal isn't reached
    while (balance < goal) {
        // add this year's payment and interest
        balance += payment;/*from  ww w .  j  av a2s . c  om*/
        double interest = balance * interestRate / 100;
        balance += interest;
        years++;
    }

    System.out.println("You can retire in " + years + " years.");
}

---

From source file:MainClass.java

public static void main(String args[]) throws IOException {
    // Write output to a file.
    FileWriter fout = new FileWriter("test.txt");
    fout.write("2 3.4 5 6 7.4 9.1 10.5 done");
    fout.close();/*from   w w  w  .j  av  a  2s.co m*/

    FileReader fin = new FileReader("Test.txt");

    Scanner src = new Scanner(fin);

    // Read and sum numbers.
    while (src.hasNext()) {
        if (src.hasNextDouble()) {
            System.out.println(src.nextDouble());
        } else {
            break;
        }
    }
    fin.close();
}

---

From source file:Calculator.java

public static void main(String[] args) {
    System.out.println("type something like: 1+3");
    Scanner scanner = new Scanner(System.in);
    double n1 = Double.NaN;
    double n2 = Double.NaN;
    String operation = null;/*from  w ww  .j a v  a 2s  .c o  m*/

    try {
        n1 = scanner.nextDouble();
        operation = scanner.next();
        n2 = scanner.nextDouble();
        double result = calculate(n1, n2, operation);
        System.out.printf("%s %s  %s  = %.2f%n", n1, operation, n2, result);
    }

    catch (Exception e) {
        System.out.println("An invalid expression.");
    }
}

---

From source file:Main.java

public static void main(String args[]) throws IOException {

    int count = 0;
    double sum = 0.0;

    FileWriter fout = new FileWriter("test.txt");

    fout.write("2, 3.4,    5,6, 7.4, 9.1, 10.5, done");
    fout.close();/*from  w w w .ja  v  a 2  s .  c o  m*/

    FileReader fin = new FileReader("Test.txt");

    Scanner src = new Scanner(fin);

    src.useDelimiter(", *");

    while (src.hasNext()) {
        if (src.hasNextDouble()) {
            sum += src.nextDouble();
            count++;
        } else {
            String str = src.next();
            if (str.equals("done"))
                break;
            else {
                System.out.println("File format error.");
                return;
            }
        }
    }

    fin.close();
    System.out.println("Average is " + sum / count);
}

---

From source file:MainClass.java

public static void main(String args[]) throws IOException {
    int count = 0;
    double sum = 0.0;

    FileWriter fout = new FileWriter("test.txt");

    fout.write("2, 3.4,    5,6, 7.4, 9.1, 10.5, done");
    fout.close();/*from   w ww .ja v  a2  s .c om*/

    FileReader fin = new FileReader("Test.txt");

    Scanner src = new Scanner(fin);

    src.useDelimiter(", *");

    while (src.hasNext()) {
        if (src.hasNextDouble()) {
            sum += src.nextDouble();
            count++;
        } else {
            String str = src.next();
            if (str.equals("done"))
                break;
            else {
                System.out.println("File format error.");
                return;
            }
        }
    }

    fin.close();
    System.out.println("Average is " + sum / count);
}

---

From source file:MainClass.java

public static void main(String args[]) {
    Scanner conin = new Scanner(System.in);

    int count = 0;

    System.out.println("Enter numbers to average.");

    while (conin.hasNext()) {
        if (conin.hasNextDouble()) {
            System.out.println(conin.nextDouble());
            count++;//from w w  w .j a va2  s  .c  o m
        }
        if (count == 3) {
            System.exit(0);

        }
    }

}

---

From source file:MainClass.java

public static void main(String args[]) {
    Scanner conin = new Scanner(System.in);

    int count = 0;
    double sum = 0.0;

    System.out.println("Enter numbers to average.");

    while (conin.hasNext()) {
        if (conin.hasNextDouble()) {
            sum += conin.nextDouble();
            count++;//from   w ww  . jav a  2s  . co  m
        } else {
            String str = conin.next();
            if (str.equals("done"))
                break;
            else {
                System.out.println("Data format error.");
                return;
            }
        }
    }

    System.out.println("Average is " + sum / count);
}

---

From source file:MainClass.java

public static void main(String args[]) throws IOException {
    // Write output to a file.
    FileWriter fout = new FileWriter("test.txt");
    fout.write("int: 1  double 1.0  boolean true");
    fout.close();// w w  w.  j a va2s .c o  m

    FileReader fin = new FileReader("Test.txt");

    Scanner src = new Scanner(fin);

    while (src.hasNext()) {
        if (src.hasNextInt()) {
            System.out.println("int: " + src.nextInt());
        } else if (src.hasNextDouble()) {
            System.out.println("double: " + src.nextDouble());
        } else if (src.hasNextBoolean()) {
            System.out.println("boolean: " + src.nextBoolean());
        } else {
            System.out.println(src.next());
        }
    }
    fin.close();
}

---

• «
• 1
• 2
• 3
• 4
• 5
• »