使用 R 绘制带有等高线图叠加的 3D 曲面图 [英] Plotting a 3D surface plot with contour map overlay, using R

问题描述

我有一个 3 元组数据集(X、Y、Z 点)，我想用 R 绘制.

我想根据数据创建一个曲面图，并在曲面图上叠加一个等高线图，以便创建等高线图是曲面图的阴影"或投影的印象.等高线图将出现在曲面图下方.

我的数据集看起来有点像这样:

轴 |数据类型-------------------X |日期值是 |浮点值Z |浮点值

我怎样才能做到这一点?

解决方案

我刚刚看到您指出您的维度之一是日期.在这种情况下，

原答案:

据我所知，您希望将地图作为 3D 曲面图下方平面上的投影.我认为除了创建两个图然后将它们组合之外，没有其他简单的方法可以做到这一点.您可以

scatterplot3d

scatterplot3d 有点像 R 中的其他绘图函数(阅读小插图).这是一个简单的例子:

temp <- seq(-pi, 0, length = 50)x <- c(rep(1, 50) %*% t(cos(temp)))y <- c(cos(temp) %*% t(sin(temp)))z <- c(sin(temp) %*% t(sin(temp)))scatterplot3d(x, y, z, highlight.3d=TRUE,col.axis="blue", col.grid="lightblue",main="scatterplot3d - 2", pch=20)

在这种情况下，您需要叠加图像.R-Wiki 有一篇关于创建的好帖子一张半透明的背景图片.

I have a 3-tuple data set (X,Y,Z points) that I want to plot using R.

I want to create a surface plot from the data, and superimpose a contour map on the surface plot, so as to create the impression of the contour map being the "shadow" or projection from the surface plot. The contour map is to appear below the surface plot.

My data set looks somewhat like this:

Axis  |  Data Type
-------------------
X     |  Date value
Y     |  Float value
Z     |  Float value

How can I achieve this?

解决方案

Edit:

I just saw that you pointed out one of your dimensions is a date. In that case, have a look at Jeff Ryan's chartSeries3d which is designed to chart 3-dimensional time series. Here he shows the yield curve over time:

Original Answer:

As I understand it, you want a countour map to be the projection on the plane beneath the 3D surface plot. I don't believe that there's an easy way to do this other than creating the two plots and then combining them. You may find the spatial view helpful for this.

There are two primary R packages for 3D plotting: rgl (or you can use the related misc3d package) and scatterplot3d.

rgl

The rgl package uses OpenGL to create interactive 3D plots (read more on the rgl website). Here's an example using the surface3d function:

library(rgl)
data(volcano)
z <- 2 * volcano # Exaggerate the relief
x <- 10 * (1:nrow(z)) # 10 meter spacing (S to N)
y <- 10 * (1:ncol(z)) # 10 meter spacing (E to W)
zlim <- range(z)
zlen <- zlim[2] - zlim[1] + 1
colorlut <- terrain.colors(zlen,alpha=0) # height color lookup table
col <- colorlut[ z-zlim[1]+1 ] # assign colors to heights for each point
open3d()
rgl.surface(x, y, z, color=col, alpha=0.75, back="lines")

The alpha parameter makes this surface partly transparent. Now you have an interactive 3D plot of a surface and you want to create a countour map underneath. rgl allows you add more plots to an existing image:

colorlut <- heat.colors(zlen,alpha=1) # use different colors for the contour map
col <- colorlut[ z-zlim[1]+1 ] 
rgl.surface(x, y, matrix(1, nrow(z), ncol(z)),color=col, back="fill")

In this surface I set the heights=1 so that we have a plane underneath the other surface. This ends up looking like this, and can be rotated with a mouse:

scatterplot3d

scatterplot3d is a little more like other plotting functions in R (read the vignette). Here's a simple example:

temp <- seq(-pi, 0, length = 50)
x <- c(rep(1, 50) %*% t(cos(temp)))
y <- c(cos(temp) %*% t(sin(temp)))
z <- c(sin(temp) %*% t(sin(temp)))
scatterplot3d(x, y, z, highlight.3d=TRUE,
 col.axis="blue", col.grid="lightblue",
 main="scatterplot3d - 2", pch=20)

In this case, you will need to overlay the images. The R-Wiki has a nice post on creating a tanslucent background image.

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