#include <stdio.h>
#include <math.h>

void cquad (double a, double b, double c, int nq, double *x, double *quad)
{
  int i;
/*
 *  Calculate quadratic polynomial values.
 */
  for(i = 0; i < nq; i++) {
    quad[i] = a * (x[i] * x[i]) + b * x[i] + c;
  }
}

double arcln (int numpnt, double *pointx, double *pointy)
{
  int i;
  double arcln, pdist;

/*
 *  Calculate arc lengths.
 */
  if (numpnt < 2) {
    printf("arcln: Number of points must be at least 2");
    exit();
  }
  
  arcln = 0.;
  for(i = 1; i < numpnt; i++) {
    pdist = sqrt(pow(pointx[i]-pointx[i-1],2) + pow(pointy[i]-pointy[i-1],2));
    arcln = arcln + pdist;
  }
  return(arcln);
}