// poly.h   polyprt  polycopy  polyval  polyderiv  polyintegrate
//          polyadd  polysub  polymul  polydiv  polyshrink
//          polymake  polyfindaroot  polyremovearoot polyroots
//          polyfit
//          polynomial stored  p[pwr]*x^pwr + ... + p[2]*x^2 + p[1]*x + p[0]
//          some functions require passing array or address of pwr for return

double polyval(int pwr, double p[], double x);
void polycopy(int pwr, double pin[], double pouy[]);
void polyprt(int pwr, double p[]);
void polyderiv(int pwr, double p[], double pderiv[]);
void polyintegrate(int pwr, double p[], double pintg[]);
void polyadd(int npp, double p[], int npq, double q[], int npr[], double r[]);
void polysub(int npp, double p[], int npq, double q[], int npr[], double r[]);
void polymul(int npp, double p[], int npq, double q[], int npr[], double r[]);
void polydiv(int npp, double p[], int npd, double d[],
	     int npq[], double q[], int npr[], double r[]);
int polyshrink(int pwr, double p[]);
void polymake(int nr, double x[], int npp[], double p[]);
double polyfindaroot (int npp, double p[]);
void polyremovearoot(double x, int npp[], double p[]);
void polyroots(int npp, double p[], int nr, double x[]);

// fit polynomial to data
void   polyfit(int pwr, int n, double x[], double y[], double p[]);