Why my program cannot calculate the decimal value?

[pearllymary78]

Hi, newbie here just learning to get use of java.
I wan my program to calculate an output when user keyin an input number and round the output number to 7 decimal places.
The formula I use below in my program:
y=(x*1.5/2048)-0.80

My program can be compiled with no error.
However, when I keyin an input number, it cannot be calculated.
For example, when I keyin a number "1107" or any other decimal values like (1107.07)
It shows the errors below:

Enter input number: 1107
Output is Exception in thread "main" java.util.IllegalFormatConversionException:
d != java.lang.Double
at java.util.Formatter$FormatSpecifier.failConversion (Formatter.java:399
2)
at java.util.Formatter$FormatSpecifier.printInteger(F ormatter.java:2708)

at java.util.Formatter$FormatSpecifier.print(Formatte r.java:2660)
at java.util.Formatter.format(Formatter.java:2432)
at java.io.PrintStream.format(PrintStream.java:920)
at java.io.PrintStream.printf(PrintStream.java:821)
at MyFormula.main(MyFormula.java:22)

The program is below,

import java.util.Scanner; 

public class MyFormula
{

   public static void main( String args[] )
   {

      Scanner input = new Scanner( System.in );

      double input_num;
      double output_num;


      System.out.print( "Enter input number: " ); 
      input_num = input.nextInt(); 

      output_num = (input_num*1.5/2048)-0.80;

      System.out.printf( "Output is %d\n", output_num ); 

   } 

}

What's wrong actually? Hope I could find an expert here to guide. Thank you.

[Nicholas Jordan]

You are calling next Integer when the datatype is double.

while(input. hasNextFloat()){
//......

[pearllymary78]

I am having trouble with input.nextInt(). Where should I correct my code?

[Fubarable]

For cripes sake, there's only one place you're calling nextInt. Can't you figure that out?

[hardwired]

        Scanner input = new Scanner( System.in );

        double input_num;  // declaration
        double output_num;

        System.out.print( "Enter input number: " );
        // "input_num" is declared as type [i]double[/i]
        // so you will have trouble if you try to read
        // a [i]double[/i] with the [i]nextInt[/i] method. Use
        // [i]nextDouble[/i]
        input_num = input.nextDouble(); 

        output_num = (input_num*1.5/2048)-0.80;

        // You want to print type [i]double[/i] here
        // so you must specify a floating point format (%f)
        // instead of integer format (%d).
        System.out.printf( "Output is %.3f\n", output_num );