code: public void build(double[] coords, int nump) throws IllegalArgumentException {
          if (nump < 4) {
              throw new IllegalArgumentException("Less than four input points specified");
          }
          if (coords.length / 3 < nump) {
              throw new IllegalArgumentException("Coordinate array too small for specified number of points");
          }
          initBuffers(nump);
          setPoints(coords, nump);
          buildHull();
      }
docs: Constructs the convex hull of a set of points whose coordinates are given
  by an array of doubles.
  
  @param coords
  x, y, and z coordinates of each input point. The length of
  this array must be at least three times <code>nump</code>.
  @param nump
  number of input points
  @throws IllegalArgumentException
  the number of input points is less than four or greater than
  1/3 the length of <code>coords</code>, or the points appear
  to be coincident, colinear, or coplanar.