Documentation Center

  • Trial Software
  • Product Updates

Contours

Contours of an implicit function

Value Summary

MandatoryList of arithmetical expressions

Graphics Primitives

ObjectsContours Default Values
plot::Implicit2d, plot::Implicit3d[0]

Description

With Contours, you can set the contour(s) of an implicit function.

By default, plot::Implicit2d and plot::Implicit3d plot the set . Using Contours, you can instead plot the set for any real c or for a sequence of such values.

Examples

Example 1

The following command plots a series of cuts through a sphere:

plot(plot::Implicit2d(x^2+y^2, x = -1..1, y = -1..1,
                      Contours = [0, 0.25^2, 0.5^2, 
                                  0.75^2, 1.0])):

Example 2

Being an expression attribute, Contours can be animated:

plot(plot::Implicit2d(x^2-y^2, x = -1..1, y = -1..1,
                Contours = [1/2*cos(a)], a=0..2*PI)):

Example 3

The contour currently plotted is passed to the color functions and can be used to distinguish them visually:

plot(plot::Implicit3d(x^y - y*z, x=1..4, y=1..4, z=-2..2,
                      Contours = [$0..5],
                      FillColorFunction = ((x,y,z,dx,dy,dz,c) ->
                                           RGB::ColorList[round(c)+1])))

Was this topic helpful?