Math- Small Sample Tests

 

#include <bits/stdc++.h>

using namespace std;

int t_test(void){

    /* Will ask the user for the type of question and will generate the 

     * value of t_calc according to the case

     */

     

     // T-Calculated

     float t_calc=0;

     int choice=0;

     cout<<"T-test for One Sample: 1\n"<<"T-test for 2 Sample(independent): 2\n"<<"T-test for 2 Sample(dependent): 3\n"<<"T-test for Correlation Coefficient: 4\n";

     cout<<"Enter your choice: ";

     int chk_repeat=0;

     foo:

     

     if(chk_repeat==1)cout<<"Shove off boy...\n";

     if(chk_repeat==2)cout<<"What are you doing man? Enter a valid choice!\n";

     if(chk_repeat==3)cout<<"Seriously? Are you soo free? Valid choice?\n";

     if(chk_repeat==4)cout<<"I am out now, you continue...\n";

     cin>>choice;

     cout<<endl;

     

     // Variables for 1st Case

     vector<float> data;

     float t_tab=0,mean=0,q_mean=0,sD=0,n=0,sum=0;

     float sum2=0;

     // Variables for 2nd Case

     vector<float> data2;

    float sum_data2=0,sum1=0;

    float mean_d2=0;

    int n1=0,n2=0;

     switch(choice){

         

         case 1:

        // For One Sample Case

            cout<<"Enter the size of the data: ";

            cin>>n;

            cout<<"Enter the value of given mean in question(meu): ";

            cin>>q_mean;

            cout<<endl<<"Enter the value of t_tab: ";

            cin>>t_tab;

            cout<<endl<<"Now Enter the values of x(space separated):\n";

            for(int i=0;i<n;i++){

                float temp;

                cin>>temp;

                sum+=temp;

                data.push_back(temp);

            }

            // Calculate mean

            

            mean=sum/n;

            cout<<"mean is "<<mean<<endl;

            // Now Standard Deviation

            for(int i=0;i<n;i++){

                sum2+=(data[i]-mean)*(data[i]-mean);   

            }

            sD=sqrt(sum2/(n-1));

            cout<<"sD is "<<sD<<endl;

            // Now will just use the formula of t_calc

            t_calc=((mean-q_mean)/sD)*sqrt(n);

            cout<<"t_calc is "<<t_calc<<endl;

            cout<<((abs(t_calc)<t_tab)?"Null Hypothesis!\n":"Alternate Hypothesis\n");

            return t_calc;

            break;

        case 2:

        // 2 Sample independent

            

            cout<<"Enter the value of n1: ";

            cin>>n1;

            cout<<endl<<"Enter the value of n2: ";

            cin>>n2;

            // cout<<endl;

            // cout<<"Enter the value of given mean in question(meu): ";

            // cin>>q_mean;

            cout<<endl<<"Enter the value of t_tab: ";

            cin>>t_tab;

            cout<<endl<<"Now Enter the data1:\n";

            for(int i=0;i<n1;i++){

                float temp;

                cin>>temp;

                sum+=temp;

                data.push_back(temp);

            }

            mean=sum/n1;

            cout<<"mean1 is "<<mean;

            cout<<endl<<"Now Enter the data2:\n";

            for(int i=0;i<n2;i++){

                float temp;

                cin>>temp;

                sum_data2+=temp;

                data2.push_back(temp);

                // data2[i]=temp;

            }

            // Calculate mean

            

            mean_d2=sum_data2/n2;

            cout<<"mean_d2 is "<<mean_d2<<endl;

            // Now Standard Deviation

            //sum2: summation of square of difference of x2-x2_mean

            for(int i=0;i<n2;i++){

                sum2+=(data2[i]-mean_d2)*(data2[i]-mean_d2);   

            }

            cout<<"sum2 is "<<sum2<<endl;

            // Now for x1

            for(int i=0;i<n1;i++){

                sum1+=(data[i]-mean)*(data[i]-mean);

            }

            cout<<"sum is "<<sum1<<endl;

            // sD=sqrt(sum2/(n-1));

            sD=sqrt((sum1+sum2)/(n1+n2-2));

            cout<<"sD is "<<sD<<endl;

            // Now will just use the formula of t_calc

            // t_calc=((mean-q_mean)/sD)*sqrt(n);

            t_calc=((mean-mean_d2)/sD)*sqrt((n1*n2)/(n1+n2));

            cout<<"t_calc is "<<t_calc<<endl;

            cout<<((abs(t_calc)<t_tab)?"Null Hypothesis!\n":"Alternate Hypothesis\n");

            return t_calc;

            break;

        case 3:

            

             break;

        case 4:

             // Currently I am not handling the case of 

             // Correlation Coefficient

             break;

        default:

            cout<<"Please select a valid choice!\n";

            chk_repeat+=1;

            goto foo;

     }

     return t_calc;

    

}

int main() {

    t_test();

    return 0;

}