W7_COMPUTER PROGRAMMINING 2020 SPRING

W7 Further class concepts, polymorphism, abstract class, composition, inheritance, indirect referencing, lambda variables

EX 1 Composition

import javax.swing.*;

//Composition

class f1

{ public double func(double x)

{return x*x-2.0;}

public double dfunc(double x)

{ double dx=0.001;

double df=(func(x+dx)-func(x-dx))/(2.0*dx);

return df;

}

}

public class W7Ex1

{ public static double Dinput(String s)

{ return Double.parseDouble(JOptionPane.showInputDialog(s));}

public static double secant(f1 f,double x)

{ double eps=1.e-6;

int i=0;

int nmax=100;

while(Math.abs(f.func(x))>eps && i<nmax)

{x=x-f.func(x)/f.dfunc(x);i++;}

return x;

}

public static void main(String arg[])

{ //root of a function

double x0=Dinput("x0=");

f1 f=new f1();

double x=secant(f,x0);

String s="x="+x;

JOptionPane.showMessageDialog(null,s);

}

}

import javax.swing.*;

//Composition

class f1

{

}

public class W7Ex1A

{ public static double func(double x)

{return x*x-2.0;}

public static double dfunc(double x)

{ double dx=0.001;

double df=(func(x+dx)-func(x-dx))/(2.0*dx);

return df;

}

public static double Dinput(String s)

{ return Double.parseDouble(JOptionPane.showInputDialog(s));}

public static double secant(double x)

{ double eps=1.e-6;

int i=0;

int nmax=100;

while(Math.abs(func(x))>eps && i<nmax)

{x=x-func(x)/dfunc(x);i++;}

return x;

}

public static void main(String arg[])

{ //root of a function

double x0=Dinput("x0=");

f1 f=new f1();

double x=secant(x0);

String s="x="+x;

JOptionPane.showMessageDialog(null,s);

}

}

EX2

Abstract class f_x.java

//abstract class

abstract public class f_x

{abstract public double func(double x);

public double dfunc(double x)

{ double dx=0.001;

double df=(func(x+dx)-func(x-dx))/(2.0*dx);

return df;

}

}

import javax.swing.*;

class f1 extends f_x

{ public double func(double x)

{return x*x-2.0;}

}

public class W7Ex2

{ public static double secant(f_x f,double x)

{ double eps=1.e-6;

int i=0;

int nmax=100;

while(Math.abs(f.func(x))>eps && i<nmax)

{x=x-f.func(x)/f.dfunc(x);i++;}

return x;

}

public static void main(String arg[])

{ //root of a function

double x0=W7Ex1.Dinput("x0=");

f1 f=new f1();

double x=secant(f,x0);

String s="x="+x;

JOptionPane.showMessageDialog(null,s);

}

}

import javax.swing.*;

class f2 extends f_x

{ public double func(double x)

{return x*x-x-2.0*x+5;}

}

public class W7Ex2A

{

public static void main(String arg[])

{ //root of a function

double x0=W7Ex1.Dinput("x0=");

f1 f=new f1();

double x=W7Ex2.secant(f,x0);

String s="x="+x+"\n";

f2 ff=new f2();

x=W7Ex2.secant(ff,x0);

s+="x="+x;

JOptionPane.showMessageDialog(null,s);

}

}

EX3

Interface if_x.java

interface if_x

{ public double func(double x);

//first order derivative

default double dfunc(double x)

{double dx=0.001;

double df=(func(x+dx)-func(x-dx))/(2.0*dx);

return df;

}

}

import javax.swing.*;

class f3 implements if_x

{ public double func(double x)

{return x*x-2.0;}

}

public class W7Ex3

{ public static double secant(if_x f,double x)

{ double eps=1.e-6;

int i=0;

int nmax=100;

while(Math.abs(f.func(x))>eps && i<nmax)

{x=x-f.func(x)/f.dfunc(x);i++;}

return x;

}

public static void main(String arg[])

{ //root of a function

double x0=W7Ex1.Dinput("x0=");

f3 f=new f3();

double x=secant(f,x0);

String s="x="+x;

JOptionPane.showMessageDialog(null,s);

}

}

class f4 implements if_x

{ public double func(double x)

{return x*x-x-2.0*x+5;}

}

public class W7Ex3A

{

public static void main(String arg[])

{ //root of a function

double x0=W7Ex1.Dinput("x0=");

f3 f=new f3();

double x=W7Ex3.secant(f,x0);

String s="x="+x+"\n";

f4 ff=new f4();

x=W7Ex3.secant(ff,x0);

s+="x="+x;

JOptionPane.showMessageDialog(null,s);

}

}

EX4 Lambda variables

public class W7E4

{

public static void main(String arg[])

{ //root of a function

double a=IO.Dinput("a=");

double b=IO.Dinput("a=");

if_x f=x->x*x-2.3*x-2.0;

double x0=bisection(f,a,b);

String s="x0="+x0;

IO.print(s);

}

}

import javax.swing.*;

public class W7Ex4A

{ public static double integral(if_x f,double a,double b)

{

double r[]={-0.973906528517171,-0.865063366688984,-0.679409568299024,-0.433395394129247,-0.148874338981631,

0.148874338981631,0.433395394129247,0.679409568299024,0.865063366688984,0.973906528517171};

double c[]={0.066671344308684,0.149451349150580,0.219086362515982,0.269266719309996,0.295524224714752,

0.295524224714752,0.269266719309996,0.219086362515982,0.149451349150580,0.066671344308684};

int n=r.length;

double z=0;

double x,y;

double k1=(b-a)/2.0;

double k2=(b+a)/2.0;

double y1=0;

for(int i=0;i<n;i++)

{x=k2+k1*r[i];y=f.func(x);y1=c[i]*y;z+=y1;}

return k1*z;

}

public static void main(String arg[])

{ //integral of a function

double a=W7Ex1.Dinput("a=");

double b=W7Ex1.Dinput("b=");

if_x f=x->x*x-2.0;

double I=integral(f,a,b);

String s="I="+I;

JOptionPane.showMessageDialog(null,s);

}

}

EX5 Lambda variables

interface if_xy

{public double func(double x[]);}

import javax.swing.*;

public class W7Ex4

{

public static void main(String arg[])

{ //root of a function

//root of a function

double x0=W7Ex1.Dinput("x0=");

if_x f=x->x*x-2.0;

double x=W7Ex3.secant(f,x0);

String s="x="+x;

JOptionPane.showMessageDialog(null,s);

}}

import javax.swing.*;

class f6 implements if_xy

{public double func(double z[])

{double w=z[0]*z[0]+z[1]*z[1];

return w;

}

}

public class W7Ex5A

{

public static void main(String arg[])

{ //root of a function

double x=W7Ex1.Dinput("x=");

double y=W7Ex1.Dinput("y=");

f6 f=new f6();

double z[]={x,y};

String s="x="+z[0]+"y="+z[1]+"\nx*x+y*y = "+f.func(z);

JOptionPane.showMessageDialog(null,s);

}

}

HOMEWORK EXERCISES

computer_programming@turhancoban.com

W1_turhan_coban_0101333.pdf

W3_ali_veli_02335646.pdf

W7HW1 : abstract class y_x is given calculate function value and derivative of y(x)= x*x-2.3*x-2.0;

//abstract class y_x.java

abstract public class y_x

{abstract public double func(double x);

//derivative of func

public double dfunc(double x)

{double h=0.0001;

double dy=(func(x+h)-func(x-h))/(2.0*h);

return dy;

}

}

class y1 extends y_x

{ public double func(double x)

{return x*x-2.3*x-2.0;}

}

public class W7HW1

{

public static void main(String arg[])

{

}

}

W7HW2 Interface iy_x.java is given calculate function value and derivative of y(x)= x*x-2.3*x-2.0;

@FunctionalInterface

interface iy_x

{ public double func(double x);

//first order derivative

default double dfunc(double x)

{double h=1.0e-3;

double dy=(func(x+h)-func(x-h))/(2.0*h);

return dy;

}

}

class y1 implements iy_x

{ public double func(double x)

{return x*x-2.3*x-2.0;}

}

public class W7HW2

{

public static void main(String arg[])

{

}

}

W7HW3 Interface iy_x.java is given calculate function value and derivative of y(x)= x*x-2.3*x-2.0 by using lambda variables

W7HW4 Interface iz_xy is given as

@FunctionalInterface

interface iz_xy

{public double func(double x[]);

default double[] dfunc(double x[])

{double h=1.0e-3;

int n=x.length;

double dy[]=new double[n];

double z1[]=new double[n];

double z2[]=new double[n];

for(int i=0;i<n;i++)

{ for(int j=0;j<n;j++) {z1[i]=x[i];z2[i]=x[i];}

z1[i]=x[i]+h;

z2[i]=x[i]-h;

dy[i]=(func(z1)-func(z2))/(2.0*h);

z1[i]=x[i];z2[i]=x[i];

}

return dy;

}

}

public class W7HW4

{

public static void main(String arg[])

{ }

Calculate

Z=2x+3xy+3.3*x²-1.23y²

z=2.0*x[0]+3.0*x[0]*x[1]+3.3*x[0]*x[0]-1.23*x[1]*x[1]

function value and its derivatives by using lambda variables

W7HW5 Calculate (use lambda variables)