Functions of Two Variables

This page describes the plotting of surfaces defined by an equation of two variables, z=f(x,y), for which the ranges of x and y are explicitly defined. The basic draw command for this function utilizes either the uncompiled function or compiled function format. The general format for an uncompiled function is:

       draw(f(x,y), x=a..b, y=c..d)

where a..b and c..d are segments defining the intervals [a,b] and [c,d] over which the variables x and y span. In this case, the function is not compiled until the draw command is executed. Here is an example:

In the case of a compiled function, the function is named and compiled independently. This is useful if you intend to use a function often, or if the function is long and complex. The following line shows a function whose parameters are of the type SmallFloat. The function is compiled and stored by Axiom when it is entered.

Once the function is compiled the draw command only needs the name of the function to execute. Here is a compiled function example:

Note that the parameter ranges do not take the variable names as in the case of uncompiled functions. The variables are entered in the order in which they are defined in the function specificationl. In this case the first range specifies the x-variable and the second range specifies the y-variable.