MATLAB:需要制作 4D 绘图(3D + 颜色/颜色) [英] MATLAB: Need to make a 4D plot (3D + Colour/Color)

问题描述

我需要制作一个 3D 表面，其中颜色将代表第四个变量.我知道冲浪"与我需要的很相似，但并非如此.基本上，我有以下变量:

I need to make a 3D surface where colour will represent the fourth variable. I know "surf" is SIMILAR to what I need, but that's not quite it. Basically, I have the following variables:

t = [1:m]

y = [1:n]

a = [1:o]

这些应该是三个笛卡尔坐标轴.

These should be the three Cartesian corodinate axes.

我还有一个变量 S，其维度为 m x n x o，基本上是振幅，是前三个变量的函数(即 S = f(t,y,a)).我希望这用颜色表示.

I also have a variable S that is of dimensions m x n x o, and is basically the amplitude, a function of the previous three variables (i.e. S = f(t,y,a)). I want this to be represented by colour.

总而言之，我需要一个 (t,y,a,S) 形式的图，其中前三个变量是大小不等的向量，最后一个变量是一个多维数组，其维度由前三个决定.

So to summarize, I need a graph of the form (t,y,a,S), where the first three variables are vectors of unequal sizes and the final variable is a multidimensional array whose dimensions are determined by the first three.

提前致谢.

推荐答案

SCATTER3 需要 x、y 和 z 和其他分组参数来对于单个系列是大小相同的 Nx1 向量，对于 M 系列是 NxM 矩阵.

SCATTER3 requires x, y and z and other grouping arguments to be equally-sized Nx1 vectors for a single series or NxM matrices for M series.

您拥有全空间 3D 数据.要制作大小相等的坐标向量，请使用 MESHGRID(或 NDGRID) 函数:

You have full space 3D data. To make equally-sized coordinate vectors use MESHGRID (or NDGRID) function:

[X, Y, Z] = meshgrid(t, y, a);

然后就可以使用SCATTER3了:

Then you can use SCATTER3:

scatter3( X(:), Y(:), Z(:), [], S(:) )

问题是因为它是全空间数据，如果你有很多点，scatter3 不会特别有用.

The problem is since it's full space data scatter3 will not be helpful specially if you have a lot of points.

您可能可以过滤您的 S 变量(类似于 idx = S > 0)，然后您可以绘制过滤后的数据.

You can probably filter your S variable (something like idx = S > 0), then you can plot filtered data.

如果您真的需要可视化所有数据，请查看Volume可视化 在 MATLAB 文档中.例如，我可以推荐 SLICE 函数.

If you really need to visualize all the data, look at Volume visualization in MATLAB documentation. I can recommend SLICE function, for example.

编辑

以下是小向量(m、n、o 等于 5)的全 3D 空间散点图示例，S = rand([m,n,o]);scatter3( X(:), Y(:), Z(:), [], S(:), '填充')

Here is an example of full 3D space scatter plot for small vectors (m, n, o equal to 5) with S = rand([m,n,o]); scatter3( X(:), Y(:), Z(:), [], S(:), 'filled' )

编辑 2

从你的评论到另一个答案，我发现你有 32x76050x4 矩阵.您实际上可以一次绘制一个 2D 切片.您可以使用 IMAGESC 功能在 2D 中进行，也可以使用 SLICE 功能在 3D 中进行.

From your comments to the other answer I found that you have 32x76050x4 matrix. You can actually plot 2D slice one at a time. you can do it in 2D with IMAGESC function, or in 3D with SLICE function.

试试:

imagesc(S(:,:,k))

其中 k 是从 1 到 4 的第三维数.

where k is a number from 1 to 4 for the 3rd dimension.

或者试试

slice(S, [], [], 1:size(S,3))
shading flat

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