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Message:

Polynomials Program

Posted by Mahen Mudalige on October 01, 2001 at 3:26 PM

Dear sir,
My programs objective was to add two polynomials of max degree 100 and multiply two polynomials but the program i design i could not add my coeffient
to the array i want and i dont know how to initialize the this array ? problem arises in the action methord when i try to add coeeficients..(mind you that i am not a java expert...this may be a simple question but can you please help...i dont know what to do next ?)

/*
* Author: Mahen Mudalige
* Created: August 08, 2001 00:05:43
* Modified: August 08, 2001 00:05:43
*/

import java.io.*;
import java.awt.*;
import java.util.*;

class Poly extends Frame{

public Label eq1;
public String list3s="";
public static TextArea sum;
public static TextArea pro;
public TextField eq11;
public TextField eq22;
public static TextArea eq111;
public static TextArea eq222;
public TextField maxeq1;
public TextField maxeq2;
private Button sumB;
private Button proB;
private StringTokenizer num1;
private TextField list;
/* This methad creates the Graphical User Interface of the Program */

public void makeGui(){
setLayout(new FlowLayout());
Panel top=new Panel();

Label meq1=new Label(" Max Degree of Equation 1: ? ");
add(meq1);

maxeq1=new TextField(15);
add(maxeq1);
Label eq1=new Label("Enter Equation 1: ");
add(eq1);

eq11=new TextField(20);
add(eq11);

Label meq2=new Label(" Max Degree of Equation 2: ? ");
add(meq2);

maxeq2=new TextField(15);
add(maxeq2);
Label eq2=new Label("Enter Equation 2: ");
add(eq2);
eq22=new TextField(20);
add(eq22);

TextArea eq111=new TextArea("Sum :\n ",2,50);
add(eq111);

TextArea eq222=new TextArea("Product :\n ",2,50);
add(eq222);

list=new TextField(60);
list.setEditable(false);
add(list);

sumB=new Button(" SUM ");
add(sumB);
proB=new Button(" PRODUCT ");
add(proB);

}

/* This method acompanies with the GUI interface provides basic actions */

public boolean action(Event evt,Object obj){

if(evt.target==sumB){
String eq111=eq11.getText();
String maxeq111=maxeq1.getText();
int maxeq11=Integer.parseInt(maxeq111);
Polynomial lhs=new Polynomial(maxeq11);
lhs.highPower=maxeq11;
int max1=maxeq11;
StringTokenizer num1=new StringTokenizer(eq111,",");
for(max1=max1;num1.hasMoreTokens();max1--){
String item=num1.nextToken();
int coeff=Integer.parseInt(item);
lhs.coeffArray[max1]=coeff;
max1--;
}
String eq222=eq22.getText();
String maxeq222=maxeq2.getText();
int maxeq22=Integer.parseInt(maxeq222);
Polynomial rhs=new Polynomial(maxeq22);
rhs.highPower=maxeq22;
int max2=maxeq22;
StringTokenizer num2=new StringTokenizer(eq222,",");
while(num1.hasMoreTokens()){
String item1=num2.nextToken();
int coeff1=Integer.parseInt(item1);
lhs.coeffArray[max2]=coeff1;
max2--;
}
Polynomial sum=new Polynomial();
sum=sum.operaterSum(lhs,rhs);
sum.print(sum);
}//End of if statement
if(evt.target==proB){
String eq111=eq11.getText();
Polynomial lhs=new Polynomial();
String maxeq111=maxeq1.getText();
int maxeq11=Integer.parseInt(maxeq111);
lhs.highPower=maxeq11;
int max1=maxeq11;
StringTokenizer num1=new StringTokenizer(eq111,",");
while(num1.hasMoreTokens()){
String item=num1.nextToken();
int coeff=Integer.parseInt(item);
lhs.coeffArray[max1]=coeff;
max1--;
}
String eq222=eq22.getText();
Polynomial rhs=new Polynomial();
String maxeq222=maxeq2.getText();
int maxeq22=Integer.parseInt(maxeq222);
rhs.highPower=maxeq22;
int max2=maxeq22;
StringTokenizer num2=new StringTokenizer(eq222,",");
while(num1.hasMoreTokens()){
String item1=num2.nextToken();
int coeff1=Integer.parseInt(item1);
lhs.coeffArray[max2]=coeff1;
max2--;
}
Polynomial pro=new Polynomial();
pro=pro.operaterPro(lhs,rhs);
pro.print(pro);

}//End of if statement

return true;
}//End of action methord

/* This method Handles the event Window destroy by User */

public boolean handleEvent(Event event){
if(event.id==Event.WINDOW_DESTROY)
System.exit(0);
return super.handleEvent(event);
}

/* Main method */

public static void main(String[] args){

Poly file=new Poly();
file.resize(470,320);
file.makeGui();
file.show();

}//End of the main

}//end of class

class Polynomial {

public int coeffArray[];
public int highPower;
public final static int Max_Degree=100;
public static int max1;
public static int max2;

public Polynomial(int highPower){

int coeffArray[]=new int[highPower];
//zeroPolynomial();
}
public Polynomial(){

int coeffArray[]=new int[highPower];
//zeroPolynomial();
}
public int max(int a,int b){
return a>b?a:b;
}
/*
public void zeroPolynomial(){
for(int i=0;i<=highPower;i++)
coeffArray[i]=0;
highPower=0;
} */

public Polynomial operaterSum(Polynomial lhs,Polynomial rhs){
Polynomial sum=new Polynomial();
sum.highPower=max(lhs.highPower,rhs.highPower);
for(int i=sum.highPower;i>=0;i--)
coeffArray[i]=lhs.coeffArray[i]+rhs.coeffArray[i];
return sum;
}

public Polynomial operaterPro(Polynomial lhs,Polynomial rhs){
Polynomial product=new Polynomial();

product.highPower=lhs.highPower+rhs.highPower;

if(product.highPower>Max_Degree)
System.out.println("Operater * Exceed The Max Degree ");
for(int i=0;i for(int j=0;j<=rhs.highPower;j++)
product.coeffArray[i+j]+=lhs.coeffArray[i]*rhs.coeffArray[j];

return product;
}
public void print(Polynomial q){

for(int i=highPower;i>0;i--){
Poly.eq111.setText(q.coeffArray[i]+"X^"+i+"+");
System.out.print(q.coeffArray[i]+"X^"+i+"+");
}
Poly.eq111.appendText(""+q.coeffArray[0]);
System.out.print(+q.coeffArray[0]);
System.out.println("\n");

Poly.eq111.appendText("Error");
}
}