Display Methods for Geographic Data Sets.

摘要

A pixel based contouring algorithm is described and used to display three sample world wide data sets. The use of contouring, color coding and hill shading is discussed and related to the spatial frequency content of the data. Contouring has problems in steep areas where the contour lines run together. Color coding brings out the low frequency content of the data. Hill shading brings out the high frequency content or texture. Color coding and hill shading may compliment each other when the data has a mixed high and low frequency content. Reprints. (rh)