evs@romeo.cs.duke.edu (Ed Simpson) (06/23/89)
Does anyone have any information on how to perform interpolation of an independent variable on a surface in 3-space? Here is my specific problem. I have a set of contours that describes the surface of a heart in 3 dimensions. Each contour consists of a closed polyline with 128 segments. I also have a small set of electrode locations (specified in x,y,z coordinates) that are located on the contours. For example, for some applications there are about 60 electrode locations. Each electrode has a value associated with it (e.g. voltage) that is independent of the location. I need some interpolation algorithm that will assign a voltage value to each segment endpoint in the contours. Given this I can use the endpoints to contruct polygons, color each polygon according to the voltage values of its vertices (the endpoints), and display this in 3-d. I would appreciate any information on existing software or any journal articles or library references. Thanks much, Ed. Ed Simpson e-mail by ARPANET: evs@cs.duke.edu P.O.Box 3140, Duke Univ. Medical Center, Durham, NC, USA 27710
murphy@pur-phy (William J. Murphy) (06/23/89)
In the most recent issue of the Journal of the Acoustical Society of America, there is an article by Michael R. Stinson in which he describes the process (mathematics) they used to derive the area function of the human ear canal. Assuming that there is an axis defining the centerline ls the ear canal, they used digitized cross sections taken in normal cylindrical coordinates (real world coordinates) and transformed them to the local coordinates which are cross sections perpendicular to the ear canal axis. I believe the issue is June 1989. The authors are Stinson and Lawton. Bill Murphy murphy@newton.physics.purdue.edu