To plot a plane vector field f(x,y) i + g(x,y) j , one uses the Maple command
> with(plots):
> fieldplot([f(x,y),g(x,y)],x=a..b,y=c..d);
The command fieldplot may contain various options. The possible styles of arrows in the plot are line, thin, slim, thick, with thin being the default. One may also specify the thickness of the arrows. For example,
> fieldplot([y,-x], x=-1..1,y=-1..1,arrows=slim,thickness=2);
To plot a plane curve and a plane vector field in the same plot window, one first names both plots and then uses the command display to display them together. Here is an example:
> fp:=fieldplot([y,-x],x=-2..2,y=-2..2):
> cp:=plot([cos(t),sin(t),t=0..2*Pi]):
> display(fp,cp,scaling=constrained);
The command gradplot plots the gradient field of a given function of two variables. To plot vector fields in 3-dimensional space, one uses fieldplot3d and gradplot3d.