Code:
/*
*This program will read a set of data from a file, calulate the correlation with the ok-line and
*draw the graph of the ok-line and plot the set of data on the graph
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <koolplot.h>
int main()
{
/* Define variables */
int j, xy, sl, yi, xl, xu, xp, p, n, sn;
double arrayx[50], arrayy[50], Mx, My, sumxy, sumx2, sumnx2, sumnxy, sumy2, sumny2, sumnxy2;
double sMx, sMy, ssumx2, ssumxy, ssumy2, ssumnx2, ssumny2, cor, scor;
/*Function Prototype*/
int readData(double arrayx[], double arrayy[]);
double getMx(double arrayx[], int n);
double getMy(double arrayy[], int n);
double getsumxy(double arrayx[], double arrayy[], double Mx, double My, int n);
double getsumx2(double arrayx[], double Mx, int n);
double getsumnx2(double sumx2, int n);
double getsumnxy(double sumxy, int n);
double getsumy2(double arrayy[], double My, int n);
double getsumny2(double sumy2, int n);
double getsumnxy2(double sumnx2, double sumny2);
void printResults(double scor);
void graph(double arrayx[], double arrayy[], int sl, int yi, int xl, int xu, int xy);
/* Read data from file */
xy = readData(arrayx, arrayy);
/*Enter details of Ok line*/
printf("Generating the ok-line\n");
printf("Enter the slope of ok line: ");
scanf("%d", &sl);
printf("Enter the y-intercept of the ok line: ");
scanf("%d", &yi);
printf("Enter lower bound of x value: ");
scanf("%d", &xl);
printf("Enter upper bound of x value: ");
scanf("%d", &xu);
printf("Enter the number of points to be generated: ");
scanf("%d", &p);
/*Store data from ok-line*/
n = xy+p;
for (j=xy; j<n; j++)
{
xp = j-xy;
arrayy[j] = sl*xp + yi;
}
for (j=xy; j<n; j++)
{
xp = j-xy;
arrayx[j] = xp;
}
/*Obtain values to calculate for correlation*/
Mx = getMx(arrayx, n);
My = getMy(arrayy, n);
sumxy = getsumxy(arrayx, arrayy, sMx, sMy, n);
sumx2 = getsumx2(arrayx, sMx, n);
sumnx2 = getsumnx2(ssumx2, n);
sumnxy = getsumnxy(ssumxy, n);
sumy2 = getsumy2(arrayy, sMy, n);
sumny2 = getsumny2(ssumy2, n);
sumnxy2 = getsumnxy2(ssumnx2, ssumny2);
/*End of values to calculate for correlation*/
/*Obtain value of cor*/
cor = sumnxy/sumnxy2;
/*Print results*/
printResults(scor);
/*Draw graph*/
graph(arrayx, arrayy, sl, yi, xl, xu, xy);
return 0;
}
/* Function readData
* Opens file and read data into marks array.
*
* Parameter: arrayx and arrayy - array of doubles to store data from file
*
* Return: number of entries read from file
*/
int readData(double arrayx[], double arrayy[])
{
char rdata[25];
int j, xy;
FILE *data;
printf("File name(must be typed with file type): ");
scanf("%s", &rdata);
/*Total pair of data from file*/
printf("Total data pair in file: ");
scanf("%d", &xy);
/* Open input file. */
data = fopen(rdata,"r");
/* Read data . */
for(j=0; j < (xy); j++)
{
fscanf(data, "%lf %lf", &arrayx[j], &arrayy[j]);
}
return xy;
}/*End of readData*/
/*Determine mean of x*/
double getMx(double arrayx[], int n)
{
double sumx1=0.00, Mx;
int j;
for(j = 0; j < n; j++)
{
sumx1 = sumx1 + arrayx[j];
}
Mx = sumx1/n;
return Mx;
}/*End mean of x*/
/*Determine mean of y*/
double getMy(double arrayy[], int n)
{
double sumy1=0.00, My;
int j;
for(j = 0; j < n; j++)
{
sumy1 = sumy1 + arrayy[j];
}
My = sumy1/n;
return My;
}/*End mean of y*/
/*Determine sumxy*/
double getsumxy(double arrayx[], double arrayy[], double Mx, double My, int n)
{
double sumxy;
int j;
sumxy = 0.00;
for(j=0; j < n; j++)
{
sumxy = sumxy + ((arrayx[j]) - Mx)*((arrayy[j]) - My);
}
return sumxy;
}/*End of sumxy*/
double getsumx2(double arrayx[], double Mx, int n)
{
/*Determine sumx2*/
double sumx2 = 0.00;
int j;
for(j = 0; j < n; j++)
{
sumx2 = sumx2 + ((arrayx[j] - Mx)*(arrayx[j] - Mx));
}
/*End of sumx2*/
return sumx2;
}
double getsumnx2(double sumx2, int n)
{
double sumnx2;
double c;
int j;
/*Determine sumnx2*/
sumnx2 = 0.00;
c = 0.00;
c = c + (sumx2/n);
sumnx2 = sumnx2 + sqrt(c);
return sumnx2;
}/*End of sumnx2*/
double getsumnxy(double sumxy, int n)
{
double sumnxy;
/*Determine sumnxy*/
sumnxy = 0.00;
sumnxy = sumnxy + (sumxy/n);
return sumnxy;
}/*End of sumnxy*/
double getsumy2(double arrayy[], double My, int n)
{
double sumy2;
int j;
/*Determine sumy2*/
sumy2 = 0.00;
for(j = 0; j < n; j++)
{
sumy2 = sumy2 + ((arrayy[j] - My)*(arrayy[j] - My));
}
return sumy2;
}/*End of sumy2*/
double getsumny2(double sumy2, int n)
{
/*Determine sumny2*/
double sumny2 = 0.00;
double d = 0.00;
d = d + (sumy2/n);
sumny2 = sumny2 + sqrt(d);
return sumny2;
}/*End of sumny2*/
double getsumnxy2(double sumnx2, double sumny2)
{
/*Determine sumnxy2*/
double sumnxy2 = 0.00;
sumnxy2 = sumnxy2 + (sumnx2 * sumny2);
return sumnxy2;
}/*End of sumnxy2*/
/* Function printResults
* Display the value of a, b, and cor
* Determine the status of chip
*
* Parameter: geta - the value of a
* Parameter: getb - the value of b
* Parameter: cor - the value of correlation
* return - void
*/
void printResults(double cor)
{
printf("Value of correlation is %.2lf\n", cor);
if (cor < 0.98)
{
printf("Possible chip failure\n");
}
else
{
printf("Chip is OK\n");
}
}
/*Function graph
*Draws graph of ok line and
*plots the data from the file on the graph*/
void graph(double arrayx[], double arrayy[], int sl, int yi, int xl, int xu, int xy)
{
int j;
plotdata x(xl, xu);
plotdata y = sl*x + yi;
for (j=0; j<xy; j++)
{
addMark(x, y, arrayx[j], arrayy[j]);
}
plot(x, y, BLACK, "SELF MONITORING: ok line: y = 2x + 3");
}
Originally Posted by darkconvoy
