Summary

DescriptionMonkey Saddle Surface (Shaded).png	English: A monkey saddle surface, with the equation ${\displaystyle z=x^{3}-3xy^{2}\,}$. Done in MuPAD. Русский: Поверхность Обезьянье седло, задаваемая уравнением ${\displaystyle z=x^{3}-3xy^{2}\,}$. Сделано в MuPAD.
Date	11 April 2006
Source	Own work
Author	Inductiveload
Permission (Reusing this file)	Public domainPublic domainfalsefalse I, the copyright holder of this work, release this work into the public domain. This applies worldwide. In some countries this may not be legally possible; if so: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
Other versions	Unshaded Version

MuPAD code

f := x^3-3*x*y^2:

  conts := 16:
  projectionlevel:=-1.5:

colourfunc := zip(RGB::Red, RGB::CornflowerBlue,
                  (a, b) -> (f(x,y)+1)/(2)*a
                           -(f(x,y)-1)/(2)*b):

funcplot := plot::Function3d(f(x,y),
                             x = -1..1,
                             y = -1..1,
                             Mesh = [24, 24],
                             Submesh=[8,8],
                             LineColor = RGB::Black.[0.99],
                             LineWidth = 0.1,
                             Filled = TRUE,
                             FillColorFunction = colourfunc,                             
                             AxesTitleFont = ["Courier New", 14],                       
                             ViewingBoxZRange = -1.5..1
                            ):

contours := plot::modify(funcplot,
                         ZContours = [Automatic, conts],
                         LineWidth = 0.15,
                         LineColor = RGB::Gray90.[0.5],
                         XLinesVisible = FALSE,
                         YLinesVisible = FALSE,
                         Filled = FALSE
                        ):
                        
projcontours := plot::Transform3d([0, 0, projectionlevel],
                                  [1, 0, 0, 0, 1, 0, 0, 0, 0], 
                                   plot::modify(funcplot, ZContours = [Automatic, conts],
                                                LineWidth = 0.2,
                                                LineColorType = Dichromatic,
                                                LineColor = RGB::Red.[0.99],
                                                LineColor2 = RGB::CornflowerBlue.[0.99],
                                                XLinesVisible = FALSE,
                                                YLinesVisible = FALSE,
                                                Filled = FALSE
                                               )
                                  ):
                             
camera := plot::Camera([16, -24, 30],
                       [0, 0, -0.25],
                       0.08
                      ):
                             
ploteverything := plot::Canvas(funcplot,projcontours, contours,
                               Width = 200*unit::mm, 
                               Height = 150*unit::mm, 
                               Axes = Boxed,
                               TicksVisible = FALSE ,
                               TicksLabelsVisible = FALSE,
                               AxesTitles = ["", "", ""],                                                
                               camera
                              ): 
                          
plot(ploteverything)