Re: How to modify Convex Hull program to give output as Cartesian Coordinates?
- To: mathgroup at smc.vnet.net
- Subject: [mg48788] Re: How to modify Convex Hull program to give output as Cartesian Coordinates?
- From: "Rob Pratt" <Rob.Pratt at sas.com>
- Date: Wed, 16 Jun 2004 04:55:12 -0400 (EDT)
- References: <cam6fd$qjj$1@smc.vnet.net>
- Reply-to: "Rob Pratt" <Rob.Pratt at sas.com>
- Sender: owner-wri-mathgroup at wolfram.com
"Gilmar Rodr?guez Pierluissi" <gilmar.rodriguez at nwfwmd.state.fl.us> wrote in message news:cam6fd$qjj$1 at smc.vnet.net... > Greetings Mathematica Group!: > > I use the following example, to formulate my question: > > In[1]: data2D = {{4.4, 14}, {6.7, 15.25}, {6.9, 12.8}, {2.1, 11.1}, > {9.5, 14.9},{13.2, 11.9}, {10.3, 12.3}, {6.8, 9.5}, > {3.3, 7.7}, {0.6, 5.1},{5.3, 2.4},{8.45, 4.7}, > {11.5, 9.6},{13.8, 7.3}, {12.9, 3.1}, {11, 1.1}}; > > In[2]: << DiscreteMath`ComputationalGeometry` > > In[3]: convexhull = ConvexHull[data2D] > > Out[3]: {14,6,5,2,1,4,10,11,16,15} > > My question is: > > Is there any way to modify the ConvexHull program to give the > Cartesian coordinates of the points corresponding to the values > 14,6,5,2,1,4,10,11,16,15; instead of Out[3] above? > > Thank you! In[3]: convexhull = data2D[[ConvexHull[data2D]]] Out[3]= {{13.8, 7.3}, {13.2, 11.9}, {9.5, 14.9}, {6.7, 15.25}, {4.4, 14}, > {2.1, 11.1}, {0.6, 5.1}, {5.3, 2.4}, {11, 1.1}, {12.9, 3.1}} Rob Pratt