ABSTRACT
This chapter is about a program named D_3D that allows z = F(x, y) single-valued functions of two variables to be represented graphically as surfaces, level curves, colorcoded nodes, and stem plots. D_3D also allows the gradient of the function to be graphed, alone or combined with other type of plots. ¬e program was brie²y introduced in Chapter 1 (see Figure 1.16) and is available with the book as source code (D_3D.PAS and UNIT_ D3D.PAS) and executable Œle (D_3D.EXE). Its main capabilities are as follows:
1. 3D surface plots can be represented as lines of constant x, lines of constant y, lines of constant z (i.e., raised level curves), or node points mapped on the function surface. ¬ese lines or nodes can be plotted alone or combined, while the function surface on which they are mapped can be made transparent or opaque.
