DMBI Experiment no 3

AIM- Decision tree implementation using JAVA

import java.util.*;

//Aim: To implement Decision Tree algorithm in java

class tree{

public double hd;

public double p;

char ch;

String parent;

tree(char c,int x){

ch=c;

if(x==1)

parent="outlook";

else if(x==2)

parent="temperature";

else if(x==3)

parent="humidity";

else if(x==4)

parent="windy";}}

class d_tree{

static char outlook[]={'S','S','O','R','R','R','O','S','S','R','S','O','O','R'};

static char temperature[]={'B','B','B','M','C','C','C','M','C','M','M','M','B','M'};

static char humidity[]={'H','H','H','H','N','N','N','H','N','N','N','H','N','H'};

static char windy[]={'F','T','F','F','F','T','T','F','F','F','T','T','F','T'};

static char class1[]={'N','N','P','P','P','N','P','N','P','P','P','P','P','N'};

static double G1,G2,G3,G4;

static double HD;

static double play=9.0/14.0;

static double nplay=5.0/14.0;

static double temp1,temp2;

static int row=0,column=0;

static char classify[][]=new char[10][10];

static tree cal_hd(tree t,int choice)

{double count1=0,count2=0;

if(choice==1)

{for(int i=0;i<14;++i)

{if(t.ch==outlook[i] && class1[i]=='P')

++count1;

else

if(t.ch==outlook[i] && class1[i]=='N')

++count2;}}

if(choice==2)

{for(int i=0;i<14;++i)

{if(t.ch==temperature[i] && class1[i]=='P')

++count1;

else

if(t.ch==temperature[i] && class1[i]=='N')

++count2;}}

if(choice==3)

{for(int i=0;i<14;++i)

{if(t.ch==humidity[i] && class1[i]=='P')

++count1;

else

if(t.ch==humidity[i] && class1[i]=='N')

++count2;}}

if(choice==4)

{for(int i=0;i<14;++i)

{if(t.ch==windy[i] && class1[i]=='P')

++count1;

else

if(t.ch==windy[i] && class1[i]=='N')

++count2;}}

temp1=count1/(count1+count2);

temp2=count2/(count1+count2);

t.p=(count1+count2)/14;

if(temp1==0 || temp2==0)

t.hd=0;else

t.hd=temp1*(Math.log(1/temp1)/Math.log(10))+temp2*(Math.log(1/temp2)/Math.log(10));

return t;}

static int check_if_equal(char ca[][],int cnt){

int count1=0,count2=0,count3=0;

char c1=ca[0][0],c2=ca[0][1],c3=ca[0][2];

for(int i=0;i<cnt;++i){

if(ca[i][0]==c1)

++count1;

if(ca[i][1]==c2)

++count2;

if(ca[i][2]==c3)

++count3;}

if(count1==cnt)

return 0;

else

if(count2==cnt)

return 1;

else

if(count3==cnt)

return 2;

else

return -1;}

static void compute(char ch){

char ca1[][]=new char[10][10];

char ca2[][]=new char[10][10];

char ca3[][]=new char[10][10];

int cnt1=0;

int cnt2=0;

for(int i=0;i<14;++i){

if(outlook[i]==ch){

ca1[cnt1][0]=temperature[i];

ca1[cnt1][1]=humidity[i];ca1[cnt1][2]=windy[i];

ca1[cnt1][3]=class1[i];

++cnt1;}}

int check1=0,check2=0;

for(int i=0;i<cnt1;++i){

if(ca1[i][3]=='P')

++check1;

else

if(ca1[i][3]=='N')

++check2;

if(check1==cnt1){

classify[row][column++]=ch;

classify[row][column++]='P';

System.out.print("--------->PLAY");

return;}

else

if(check2==cnt1){

classify[row][column++]=ch;

classify[row][column++]='N';

System.out.print("--------->NO PLAY");

return;}}

//end of for loop

/*System.out.println("The array containing outlook value ch");

for(int i=0;i<9;++i){

for(int j=0;j<9;++j){

System.out.print(" "+ca1[i][j]);}

System.out.println();}*/

//The array containing outlook value ch and class1=P

cnt1=0;

for(int i=0;i<10;++i){

if(ca1[i][3]=='P'){

ca2[cnt1][0]=ca1[i][0];

ca2[cnt1][1]=ca1[i][1];

ca2[cnt1][2]=ca1[i][2];

ca2[cnt1][3]=ca1[i][3];

++cnt1;}}

classify[row][column++]=ch;

int z=check_if_equal(ca2,cnt1);

//System.out.println("The value of Z is "+z);

if(z==0){

System.out.print("\n--------->TEMPERATURE("+ca2[0][0]+")--------->PLAY\n");

classify[row][column++]=ca2[0][0];

classify[row][column++]='P';}

else

if(z==1){

System.out.print("\n--------->HUMIDITY("+ca2[0][1]+")--------->PLAY\n");

classify[row][column++]=ca2[0][1];

classify[row][column++]='P';}

else

if(z==2){

System.out.print("\n--------->WINDY("+ca2[0][2]+")--------->PLAY\n");

classify[row][column++]=ca2[0][2];

classify[row][column++]='P';}

System.out.println("The array containing ch and play");

for(int i=0;i<9;++i){

for(int j=0;j<9;++j){

System.out.print(" "+ca2[i][j]);}

System.out.println();}

//The array containing outlook value ch and class1=N

cnt1=0;

for(int i=0;i<10;++i){

if(ca1[i][3]=='N'){

ca3[cnt1][0]=ca1[i][0];

ca3[cnt1][1]=ca1[i][1];

ca3[cnt1][2]=ca1[i][2];

ca3[cnt1][3]=ca1[i][3];

++cnt1;}}

++row;

column=0;

classify[row][column++]=ch;

z=check_if_equal(ca3,cnt1);

if(z==0){

System.out.print("--------->TEMPERATURE("+ca3[0][0]+")--------->NO PLAY");

classify[row][column++]=ca3[0][0];

classify[row][column++]='N';}

else

if(z==1){

System.out.print("--------->HUMIDITY("+ca3[0][1]+")--------->NO PLAY");

classify[row][column++]=ca3[0][1];

classify[row][column++]='N';}

else

if(z==2){

System.out.print("--------->WINDY("+ca3[0][2]+")--------->NO PLAY");

classify[row][column++]=ca3[0][2];

classify[row][column++]='N';}

/*System.out.println("The array containing ch and not play");

for(int i=0;i<9;++i){

for(int j=0;j<9;++j){

System.out.print(" "+ca3[i][j]);}

System.out.println();}}

public static void main(String args[]){

Scanner scr=new Scanner(System.in);

HD=play*(Math.log(1/play)/Math.log(10))+nplay*(Math.log(1/nplay)/Math.log(10));

System.out.println("\nThe value of H(D) is "+HD);

tree sunny=new tree('S',1);

tree overcast=new tree('O',1);

tree rain=new tree('R',1);

tree hot=new tree('B',2);

tree mild=new tree('M',2);

tree cool=new tree('C',2);

tree high=new tree('H',3);

tree normal=new tree('N',3);

tree tru=new tree('T',4);

tree fal=new tree('F',4);

sunny=cal_hd(sunny,1);

overcast=cal_hd(overcast,1);

rain=cal_hd(rain,1);

hot=cal_hd(hot,2);

mild=cal_hd(mild,2);

cool=cal_hd(cool,2);

high=cal_hd(high,3);

normal=cal_hd(normal,3);

tru=cal_hd(tru,4);

fal=cal_hd(fal,4);

G1=HD-(sunny.p*sunny.hd+overcast.p*overcast.hd+rain.p*rain.hd);

G2=HD-(hot.p*hot.hd+mild.p*mild.hd+cool.p*cool.hd);

G3=HD-(high.p*high.hd+normal.p*normal.hd);

G4=HD-(tru.p*tru.hd+fal.p*fal.hd);

int gflag=0;

System.out.println("\nGain(D,Outlook)= "+G1 +"\nGain(D,Temperature)= "+G2+"\nGain(D,Humidity)= "+G3+"\nGain(D,Windy)= "+G4);

System.out.print("\nThe Splitting factor is ");

if(G1>G2 && G1>G3 && G1>G4)

System.out.println("Outlook");

else

if(G2>G1 && G2>G3 && G2>G4)

System.out.println("Temperature");

else

if(G3>G2 && G3>G1 && G3>G4)

System.out.println("Humidity");

else

if(G4>G2 && G4>G3 && G4>G1)

System.out.println("Windy");

System.out.println("\nThe Tree is as follows:-");

System.out.print("\nOUTLOOK(S)");

compute('S');

++row;

column=0;

System.out.print("\n\n\nOUTLOOK(O)");

compute('O');

++row;

column=0;

System.out.print("\n\n\nOUTLOOK(R)");

compute('R');

char input[]=new char[4];

String s;

System.out.println("\nMenu:\n\nOutlook: Sunny=S Overcast=O Rainy=R\n\nTemperature: Hot=B Medium=M Cool=C\n\nHumidity: High=H Normal=N\n\nWindy: True=T False=F");

System.out.println("\n\nEnter your new tuple to be classified ");

System.out.print("\nOutlook(S/O/R)= ");

s=scr.nextLine();

input[0]=s.charAt(0);

System.out.print("\nTemperature(B/M/C)= ");

s=scr.nextLine();

input[1]=s.charAt(0);

System.out.print("\nHumidity(H/N)= ");

s=scr.nextLine();

input[2]=s.charAt(0);

System.out.print("\nWindy(T/F)= ");

s=scr.nextLine();

input[3]=s.charAt(0);

/* Display classify

for(int i=0;i<9;++i){

for(int j=0;j<9;++j){

System.out.print(" "+classify[i][j]);}

System.out.println();}

System.out.print("Your input is ");

for(int i=0;i<4;++i)

System.out.print(" "+input[i]);

int inc1=0;

do{

if(input[0]==classify[inc1][0]){

if(classify[inc1][1]=='P')   {

   System.out.println("\n\nTuple classified as PLAY");

   break;   }

else

if(input[1]==classify[inc1][1] || input[2]==classify[inc1][1] || input[3]==classify[inc1][1])

{   if(classify[inc1][2]=='P') {

  System.out.println("\n\nTuple classified as PLAY");

  break;  }

  else

  if(classify[inc1][2]=='N')   {

  System.out.println("\n\nTuple classified as NO PLAY");

  break;

  }}}++inc1;}

while(true);}}

OUTPUT1

C:\Users\Aditya\Desktop\aditya>java d_tree

The value of H(D) is 0.2830542780615224

Gain(D,Outlook)= 0.07427909717678749

Gain(D,Temperature)= 0.00879686881360553

Gain(D,Humidity)= 0.04570704031674405

Gain(D,Windy)= 0.014487679755121663

The Splitting factor is Outlook

The Tree is as follows:-

OUTLOOK(S)

--------->HUMIDITY(N)--------->PLAY

--------->HUMIDITY(H)--------->NO PLAY

OUTLOOK(O)--------->PLAY

OUTLOOK(R)

--------->WINDY(F)--------->PLAY

--------->WINDY(T)--------->NO PLAY

Menu:

Outlook: Sunny=S Overcast=O Rainy=R

Temperature: Hot=B Medium=M Cool=C

Humidity: High=H Normal=N

Windy: True=T False=F

Enter your new tuple to be classified

Outlook(S/O/R)= S

Temperature(B/M/C)= M

Humidity(H/N)= N

Windy(T/F)= T

Your input is  S M N T

Tuple classified as PLAY