# Placing a ContourPlot under a Plot3D

I would like to combine a 3-dimensional graph of a function with its 2-dimensional contour-plot underneath it in a professional way. But I have no idea how to start.

I have a three of these I would like to make, so I don't need a fully automated function that does this. A giant block of code would be just fine.

The two plots I would like to have combined are:

potential1 =
Plot3D[-3600. h^2 + 0.02974 h^4 - 5391.90 s^2 + 0.275 h^2 s^2 + 0.125 s^4,
{h, -400, 400}, {s, -300, 300}, PlotRange -> {-1.4*10^8, 2*10^7},
ClippingStyle -> None, MeshFunctions -> {#3 &}, Mesh -> 10,
MeshStyle -> {AbsoluteThickness[1], Blue}, Lighting -> "Neutral",
MeshShading -> {{Opacity[.4], Blue}, {Opacity[.2], Blue}}, Boxed -> False,
Axes -> False]


and

contourPotentialPlot1 =
ContourPlot[-3600. h^2 + 0.02974 h^4 - 5391.90 s^2 + 0.275 h^2 s^2 + 0.125 s^4,
{h, -400, 400}, {s, -300, 300}, PlotRange -> {-1.4*10^8, 2*10^7},
Contours -> 10, ContourStyle -> {{AbsoluteThickness[1], Blue}}, Axes -> False,
PlotPoints -> 30]


These two plots look like:

I would also love it if I could get 'grids' on the sides of the box like in http://en.wikipedia.org/wiki/File:GammaAbsSmallPlot.png

Update The new plotting routine SliceContourPlot3D was introduced in version 10.2. If this function can be used to achieve the task above, how can it be done?

• For the grids look up FaceGrids in the docs. – kglr Nov 19 '12 at 1:43
• Looks like you want something like this: mathematica.stackexchange.com/q/7772/5 (see Jens' answer) – rm -rf Nov 19 '12 at 1:46

Strategy is simple texture map 2D plot on a rectangle under your 3D surface. I took a liberty with some styling that I like - you can always come back to yours.

contourPotentialPlot1 = ContourPlot[-3600. h^2 + 0.02974 h^4 - 5391.90 s^2 +
0.275 h^2 s^2 + 0.125 s^4, {h, -400, 400}, {s, -300, 300},
PlotRange -> {-1.4*10^8, 2*10^7}, Contours -> 15, Axes -> False,
PlotPoints -> 30, PlotRangePadding -> 0, Frame -> False, ColorFunction -> "DarkRainbow"];

potential1 = Plot3D[-3600. h^2 + 0.02974 h^4 - 5391.90 s^2 + 0.275 h^2 s^2 +
0.125 s^4, {h, -400, 400}, {s, -300, 300},
PlotRange -> {-1.4*10^8, 2*10^7}, ClippingStyle -> None,
MeshFunctions -> {#3 &}, Mesh -> 15, MeshStyle -> Opacity[.5],
MeshShading -> {{Opacity[.3], Blue}, {Opacity[.8], Orange}}, Lighting -> "Neutral"];

level = -1.2 10^8; gr = Graphics3D[{Texture[contourPotentialPlot1], EdgeForm[],
Polygon[{{-400, -300, level}, {400, -300, level}, {400, 300, level}, {-400, 300, level}},
VertexTextureCoordinates -> {{0, 0}, {1, 0}, {1, 1}, {0, 1}}]}, Lighting -> "Neutral"];

Show[potential1, gr, PlotRange -> All, BoxRatios -> {1, 1, .6}, FaceGrids -> {Back, Left}]


You can see I used PlotRangePadding -> 0 option in ContourPlot. It is to remove white space around the graphics to make texture mapping more precise. If you need utmost precision you can take another path. Extract graphics primitives from ContourPlot and make them 3D graphics primitives. If you need to color the bare contours - you could replace Line by Polygon and do some tricks with FaceForm based on a contour location.

level = -1.2 10^8;
pts = Append[#, level] & /@ contourPotentialPlot1[[1, 1]];
cts = Cases[contourPotentialPlot1, Line[l_], Infinity];
cts3D = Graphics3D[GraphicsComplex[pts, {Opacity[.5], cts}]];

Show[potential1, cts3D, PlotRange -> All, BoxRatios -> {1, 1, .6},
FaceGrids -> {Bottom, Back, Left}]


A simpler version but not as nice as Vitally's is this:

potential1 /.
Graphics3D[gr_, opts___] :>
Graphics3D[{gr, Scale[gr, {1, 1, 1/100}, {0, 0, -2 10^8}]},
PlotRange -> All, opts]


This can also be "projected" onto the other sides.

potential1 /.
Graphics3D[gr_, opts___] :>
Graphics3D[{gr, Scale[gr, {1, 1, 1/100}, {0, 0, -2 10^8}],
Scale[gr, {1/100, 1, 1}, {-400, 0, 0}]}, PlotRange -> All, opts]


• +1 Neat trick ;) For good graphics quality keep PlotPoints option high in this case for original surface - like around 50 or more. – Vitaliy Kaurov Nov 19 '12 at 6:21
• @VitaliyKaurov True, I have corrected that now. Looks nicer. – Matariki Nov 19 '12 at 6:55
• +1 I used that trick in this question about drop shadows, too. If you want to project along a direction that's not parallel to the axes, there's just the additional complication that the scales along different axes may be different in the output of Plot3D - that's certainly the case in this potential plot. Anyway, it doesn't make a difference for a vertical projection as you did here. – Jens Nov 19 '12 at 7:31
• @Jens Didn't know about your answer. Thanks for the link. In Mathematica V2 (if memory serves right) I used a function called ShadowPlot3D that did this type of pseudo projection. – Matariki Nov 19 '12 at 8:01
• Sometimes there's more than one correct answer... – QuantumDot Nov 20 '12 at 2:29

Here's one using SliceContourPlot3D (introduced in 10.2) and Vitaliy's stylings.

f = -3600. h^2 + 0.02974 h^4 - 5391.90 s^2 + 0.275 h^2 s^2 + 0.125 s^4;

min = -1.4*10^8;
max = 2*10^7;

potential1 = Plot3D[f, {h, -400, 400}, {s, -300, 300},
PlotRange -> {min, max}, ClippingStyle -> None, MeshFunctions -> {#3 &},
Mesh -> 15, MeshStyle -> Opacity[.5],
MeshShading -> {{Opacity[.3], Blue}, {Opacity[.8], Orange}},
Lighting -> "Neutral"
]


slice = SliceContourPlot3D[f, z == min,
{h, -400, 400}, {s, -300, 300}, {z, min - 1, min + 1},
PlotRange -> {min, max}, Contours -> 15, Axes -> False,
PlotPoints -> 50, PlotRangePadding -> 0, ColorFunction -> "DarkRainbow"
]


Show[potential1, slice, PlotRange -> All, BoxRatios -> {1, 1, .6}, FaceGrids -> {Back, Left}]


• You should mention that SliceContourPlot3D is a new feature – eldo Dec 12 '15 at 16:33
• @eldo Thanks, done! – Chip Hurst Dec 12 '15 at 16:36
• It's too bad "BackPlanes" does not allow for just depicting two or one of them. – J. M. is away Dec 12 '15 at 16:37
• It is good to see how these sorts of things get easier to do as the language progresses. – Edmund Dec 13 '15 at 18:45

So late to the party but here is my take:

f[h_, s_] := -3600. h^2 + 0.02974 h^4 - 5391.90 s^2 + 0.275 h^2 s^2 + 0.125 s^4;
min = -1.4*10^8; max = 2*10^7;

contour =
ContourPlot[f[x, y], {x, -400, 400}, {y, -300, 300},
PlotRange -> {min, max}, Axes -> False, Contours -> 15,
PlotPoints -> 50, PlotRangePadding -> 0,
ColorFunction -> "DarkRainbow"]


potential1 =
Plot3D[f[h, s], {h, -400, 400}, {s, -300, 300},
PlotRange -> {min, max}, ClippingStyle -> None,
MeshFunctions -> {#3 &}, Mesh -> 15, MeshStyle -> Opacity[.5],
MeshShading -> {{Opacity[.3], Blue}, {Opacity[.8], Orange}},
PlotRange -> {Automatic, Automatic, {min, 2}},
Lighting -> "Neutral"]


Finally, both combined:

Show[potential1,
Graphics3D[contour[[1]] /. {x_Real, y_Real} :> {x, y, min}],
BoxRatios -> {1, 1, 0.6}, FaceGrids -> {Back, Left}]