Lets say we have the following fitting function:.Code:`void fit(float x[], float y[], int ndata, float sig[], int mwt, float *a, float *b, float *siga, float *sigb, float *chi2, float *q,float *r2)`

Then we haveSo basically it is saying . Why is this?Code:`for (i=1;i<=ndata;i++)`

*chi2 += SQR(y[i]-(*a)-(*b)*x[i]);

*r2 +=

Is there any easy way to obtain from so that I can use it in the program? Note that we have .