Improved Display Methods of Single-valued Functions of Two Variables

Abstract

Based on the depth-sorting hidden-line removal algorithm, new methods of producing silhouette and raised level-curve diagrams with the hidden-lines removed of single-valued functions of two variables are presented. An algorithm of generating accurate truncated representations over the z-axis of the same types of functions is also described. These methods are particularly advantageous when plotting multimodal functions, noisy data or penalized objective functions encountered in optimization problems. Since all the graphic operations are performed entirely in the 2D image-space, the methods presented are suitable for implementation in low memory hardware like hand-held calculators and field instruments.