Hi guys I have run in to a littl bit of trouble. I am writing a class called polynomial
in which i need a derivative method I have everything, just dont know how to start the derivative method. Any help will be appriciated here is the code:
-
import java.io.*;
-
import java.util.Scanner;
-
-
public class Polynomial extends UnorderedArrayList
-
{
-
Scanner sc = new Scanner(System.in);
-
//Default constructor
-
//Postcondition: An array of the size 100, and
-
// length and maxSize are set to 100
-
public Polynomial()
-
{
-
super();
-
length = 100;
-
}
-
-
//Constructor with parameter
-
//Postcondition: An array of the size specified by
-
// the parameter size is created, length and maxSize
-
// are initialized to size
-
public Polynomial(int size)
-
{
-
super(size);
-
length = size;
-
}
-
-
//copy constructor
-
public Polynomial(Polynomial right)
-
{
-
super(right);
-
}
-
-
-
//Method to copy the coefficients of the polynomial
-
//specified by the parameter right
-
//Postcondition: The coefficients of the polynomial
-
// specified by right are copied.
-
public void copy(Polynomial right)
-
{
-
super.copyList(right);
-
}
-
-
//Method to evaluate a polynomial at a given value
-
//Postcondition: The polynomial is evaluated at x and
-
// the value is returned
-
public double evaluate(double x)
-
{
-
double value = 0.0;
-
-
DoubleElement coeff = new DoubleElement();
-
-
for(int i = 0; i < length; i++)
-
{
-
coeff.makeCopy((DoubleElement) list[i]);
-
-
if(coeff.getNum() != 0.0)
-
value = value + coeff.getNum() * Math.pow(x,i);
-
}
-
-
return value;
-
}
-
-
-
//Method to add two polynomials
-
//Postcondition: This polynomial is added with the polynomial
-
// specified by the parameter right. A reference of
-
// the result is returned.
-
public Polynomial add(Polynomial right)
-
{
-
int size = max(length, right.length);
-
int i;
-
double sumCoeff;
-
-
DoubleElement coeffP = new DoubleElement();
-
DoubleElement coeffQ = new DoubleElement();
-
-
DoubleElement z;
-
-
Polynomial temp = new Polynomial(size);
-
-
for(i = 0; i < min(length, right.length); i++)
-
{
-
coeffP.makeCopy((DoubleElement) list[i]);
-
coeffQ.makeCopy((DoubleElement) right.list[i]);
-
-
sumCoeff = coeffP.getNum() + coeffQ.getNum();
-
z = new DoubleElement(sumCoeff);
-
temp.list[i] = z;
-
}
-
-
if(size == length)
-
for(i = min(length, right.length); i < length; i++)
-
temp.list[i] = list[i].getCopy();
-
else
-
for(i = min(length, right.length); i < right.length; i++)
-
temp.list[i] = right.list[i].getCopy();
-
-
return temp;
-
}
-
-
//Method to subtract two polynomials
-
//Postcondition: The polynomial specified by the
-
// parameter right is subtracted from this
-
// polynomial. A reference of the result is returned.
-
public Polynomial subtract(Polynomial right)
-
{
-
int size = max(length, right.length);
-
int i;
-
double diffCoeff;
-
double coeff;
-
-
DoubleElement coeffP = new DoubleElement();
-
DoubleElement coeffQ = new DoubleElement();
-
-
DoubleElement z;
-
-
Polynomial temp = new Polynomial(size);
-
-
for(i = 0; i < min(length, right.length); i++)
-
{
-
coeffP.makeCopy((DoubleElement) list[i]);
-
coeffQ.makeCopy((DoubleElement) right.list[i]);
-
-
diffCoeff = coeffP.getNum() - coeffQ.getNum();
-
z = new DoubleElement(diffCoeff);
-
temp.list[i] = z;
-
}
-
-
if(size == length)
-
for(i = min(length, right.length); i < length; i++)
-
temp.list[i] = list[i].getCopy();
-
else
-
for(i = min(length, right.length); i < right.length; i++)
-
{
-
z = new DoubleElement();
-
z.makeCopy((DoubleElement) right.list[i]);
-
coeff = z.getNum();
-
z.setNum(-coeff);
-
temp.list[i] = z;
-
}
-
-
return temp;
-
}
-
-
//Method to multiply two polynomials
-
//Postcondition: This polynomial is multiplied with the
-
// polynomial specified by the parameter right. A
-
// reference of the result is returned.
-
public Polynomial multiply(Polynomial right)
-
{
-
-
Polynomial temp = new Polynomial();
-
-
System.out.println("See Programming Exercise 5 at the end of the chapter.");
-
-
return temp;
-
}
-
-
//Method to read the coefficients of a polynomial
-
public void read() throws IOException
-
{
-
DoubleElement x = new DoubleElement();
-
-
System.out.println("The degree of this polynomial is: "
-
+ (length - 1));
-
for(int i = 0; i < length; i++)
-
{
-
System.out.print("Enter the coefficient of x^"
-
+ i + ": ");
-
-
double y;
-
x.setNum(y = sc.nextDouble());
-
-
list[i] = x.getCopy();
-
}
-
}
-
-
//Method to return the string containing the polynomial
-
public String toString()
-
{
-
int i;
-
int firstNonzeroCoeff = 0;
-
DoubleElement x = new DoubleElement();
-
String str = "";
-
-
for(i = 0; i < length; i++)
-
{
-
x.makeCopy((DoubleElement) list[i]);
-
-
if(x.getNum() != 0.0)
-
{
-
firstNonzeroCoeff = i;
-
break;
-
}
-
}
-
-
if(firstNonzeroCoeff < length)
-
{
-
if(firstNonzeroCoeff == 0)
-
str = list[firstNonzeroCoeff] + " ";
-
else
-
str = list[firstNonzeroCoeff] + "x^"
-
+ firstNonzeroCoeff + " ";
-
-
for(i = firstNonzeroCoeff + 1; i < length; i++)
-
{
-
x.makeCopy((DoubleElement) list[i]);
-
-
if(x.getNum() != 0.0)
-
if(x.getNum() > 0.0)
-
str += "+ " + x.getNum() + "x^" + i + " ";
-
else
-
str += "- " + -x.getNum() + "x^" + i + " ";
-
}
-
}
-
-
return str;
-
}
-
-
//Method to determine the smaller of x and y
-
//Postcondition: The smaller of x and y is returned
-
public int min(int x, int y)
-
{
-
if(x <= y)
-
return x;
-
else
-
return y;
-
}
-
-
//Method to determine the larger of x and y
-
//Postcondition: The larger of x and y is returned
-
public int max(int x, int y)
-
{
-
if(x >= y)
-
return x;
-
else
-
return y;
-
}
-
}
-
