### 19.2.4 3D surfaces for Maple compatibility

The plot3d command is a Maple-compatible way to draw a surface. It can plot the graph of a function of two variables or a surface given by a parameterization.

- To draw the graph of a function, plot3d takes three arguments:
  - func, a function or an expression involving two variables.
  - x and y, the names of the variable in the expression (if func is an expression) which can also specify a range of values for each variable.

    If func is a function, this argument is optional, and are the ranges a..b for the variables.

    If the ranges are not given, the default values are taken from the graph configuration (see Section 2.5.8).

- plot3d(func,x,y) draws the graph.
- To draw a parameterized surface, plot3d takes one mandatory argument and two optional arguments:
  - funcs, a list of three functions or three expressions involving two variables.
  - u and v, the names of the variable in the expression (if funcs is a list of expressions), which can also specify a range of values for each variable.

    If funcs is a list of functions, this argument is optional, and are the ranges a..b for the variables.

    If the ranges are not given, the default values are taken from the graph configuration (see Section 2.5.8).

- plot3d(funcs,u,v) draws the surface.

#### Examples

plot3d(x*y,x,y)

plot3d([v*cos(u),v*sin(u),v],u,v)

plot3d([v*cos(u),v*sin(u),v],u=0..pi,v=0..3)