// Fit a quadratic warping function to the given points
// in a least-squares fashion
quadratic_2d find_quadratic(const double *out, const double *x,
const double *y, int numPts)
{
int nTerms = 11;
matrix *m = matrix_alloc(nTerms, nTerms + 1);
int row, col;
int i;
quadratic_2d c;
// For each data point, add terms to matrix
for (i = 0; i < numPts; i++) {
for (row=0;row<nTerms;row++) {
double partial_Q = get_term(row, x[i], y[i]);
for (col = 0; col < nTerms; col++) {
m->coeff[row][col] += partial_Q * get_term(col, x[i], y[i]);
}
m->coeff[row][nTerms] += partial_Q * out[i];
}
}
// Now solve matrix to find coefficients
// matrix_print(m,"\nLeast-Squares Matrix:\n",stdout);
matrix_solve(m);
c.A = m->coeff[0][nTerms];
c.B = m->coeff[1][nTerms];
c.C = m->coeff[2][nTerms];
c.D = m->coeff[3][nTerms];
c.E = m->coeff[4][nTerms];
c.F = m->coeff[5][nTerms];
c.G = m->coeff[6][nTerms];
c.H = m->coeff[7][nTerms];
c.I = m->coeff[8][nTerms];
c.J = m->coeff[9][nTerms];
c.K = m->coeff[10][nTerms];
return c;
}
extern void page_rank(size_t size)
{
matrix w;
matrix_init(&w, size);
gen_web_matrix(&w);
matrix g;
matrix_init(&g, size);
gen_google_matrix(&g, &w);
matrix_free(&w);
vector p;
vector_init(&p, size);
matrix_transpose(&g);
matrix_solve(&p, &g);
vector_sort(&p);
vector_save(&p);
matrix_free(&g);
vector_free(&p);
}