cannot find symbol method
I'm relatively new to Java, since I've been programming since March. I have to do a task for a course I磎 taking on the university, but I can't find the source of an error that appears when I try to compile.
My code is the following, for class Polinomio1:
import java.io.*;
class Polinomio1 extends Polinomio{
public Polinomio1(double[]x){
super(x);
}//POLINOMIO
public Polinomio1(int x){
super (x);
}//POLINOMIO
public Polinomio1 derivada(int n){
int j=0;
while(j<=n){
for(int i=0;i<a.length;++i){
if((i+1)><a.length){
a=a[++i]*(i+1);
a[++i]=0;
}//if
else a=0;
}//for
++j;
}//while
return new Polinomio1(a);
}//Derivada
Then, I try to use the method derivada in class Tarea=3 as follows:
import java.io.*; import java.awt.*; import java.awt.event.*;
class Tarea03 extends Frame implements ActionListener{
... // Part of the code which is non-relevant for this situation
if(x.getSource()==deriv){
for(int i=0;i<N;++i){
coef2=Double.parseDouble(coef.getText());
}//for
p=new Polinomio(coef2);
int nd=Integer.parseInt(derivt.getText());//nd n鷐ero derivada
pd=p.derivada(nd);
double aa=Double.parseDouble(at.getText());//aa valor num閞ico de a
double bb=Double.parseDouble(bt.getText());//bb valor num閞ico de b
int nn=Integer.parseInt(nt.getText());//nn valor num閞ico de n puntos
Graphics G=cv.getGraphics();
pd.graficar(G,nn,aa,bb);
}//if bot髇 derivar
I would appreciate if anyone could help me.>
