java help!

[mastabri]

can you tell me what's wrong? it always goes to the error statement

package program3;

/**
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2002</p>
* <p>Company: </p>
* @author unascribed
* @version 1.0
*/

public class Main {
public static void main(String[] args) {
FormattedInput keyboard = new FormattedInput();


int a,b,c,d;
double x = 0;


System.out.println("Enter the integer coefficients:");

a = keyboard.intRead();
b = keyboard.intRead();
c = keyboard.intRead();
d = keyboard.intRead();

/* Check for non-cubic or trival answer */


if( check_input(a,b,c,d) == false )
// If it is a non cubic or has trival answer, quit the program.
System.exit(0);
/*
double y;
y=cubic(a,b,c,d,x);

double z;
z=cubic_slope(b,c,d,x);
*/
int count=1;
while(count<=1000){
x= x-(cubic(a,b,c,d,x)/cubic_slope(b,c,d,x));

if(verify_root(a,b,c,d,x)==true)
System.out.println(a+ " +" + b + " *x+" + c + " *x^2+" + d + "*x^3 has root" + x);
else
count++;
}

System.out.println(a+ " +" + b + " *x+" + c + " *x^2+" + d + " *x^3 does not converge");

}

public static double cubic(int a, int b, int c, int d,double x){

double cubic;
cubic= a + b*x + c*(x*x) + d*(x*x*x);
return cubic;



}


public static double cubic_slope(int b, int c, int d,double x){

double cubic_slope;
cubic_slope= b + 2*c*x + 3*d*(x*x);
return cubic_slope;

}

public static boolean check_input(int a, int b, int c, int d){

if (a==0){
System.out.println(a+ " +" + b + " *x+" + c + " *x^2+" + d + " *x^3 has a trivial solution");
return false;
}

if (d==0){
System.out.println(a+ " +" + b + " *x+" + c + " *x^2+" + d + " *x^3 is not a cubic");
return false;
}

return true;


}

public static boolean verify_root(int a, int b, int c, int d,double x){

boolean verify_root;

if((a + b*x + c*(x*x) + d*(x*x*x))==0){
verify_root=true;
return true;
}

return false;

}

[evildead]

what is FormattedInput? is that a class you wrote?

are you using Apple project builder to compile? try using the debugger...

What kind of errors are you getting?


is this for a begging programing class? did your professor give you some utillity classes to use? most of the time they give you some simple input classes to make things simple at first

[robbieduncan]

Need more data! What is the exact error outputted. Is it from the compiler, or when you run it. Is that the exact file or do you #include anything?

[bousozoku]

Without any more information, error message, error location, it's difficult to tell that there's a problem.

I would guess that FormattedInput needs to be imported or defined in some other way before you can use it there.

[macktheknife]

Originally posted by evildead
what is FormattedInput? is that a class you wrote?

Exactly. Where did you put this class?