Specifying Plots on Cut Planes
In two-dimensional problems, the CONTOUR, SURFACE, VECTOR, GRID output forms display data values on the computation plane.
In three dimensions, the same displays are available on any cut plane through the 3D figure. The specification of this cut plane is made by simply appending the equation of a plane to the plot command, qualified by 'ON':
CONTOUR(Phi) ON x=0
Note: More uses of the ON clause, including plots on extrusion surfaces, will be discussed later.
We can also request plots of the computation grid (and by implication the domain structure) with the GRID command:
GRID(x,z) ON y=0
This command will draw a picture of the intersection of the plot plane with the tetrahedral mesh structure currently being used by FlexPDE. The plot will be painted with colors representing the distinct material properties present in the cross-section. 3D compartments with identical properties will appear in the same color. The arguments of the GRID plot are the values to be displayed as the abscissa and ordinate positions. Deformed grids can be displayed merely by modifying the arguments.