plotting - Making a ListVectorPlot3D from data in an external file

I have a .dat file with six columns: {x y z vx vy vz}, where x, y, z are space coordinates and vx, vy, vz are the vector components.

How can I use this file to get a ListVectorPlot3D image? Because I tried to arrange the data as {{x,y,z}, {vx,vy,vz}} and Mathematica still gives me an error message:

ListVectorPlot3D::vfldata ... is not a valid vector field dataset or a valid list of datasets.

I haven't found many related question about this, just one about using Graphics and drawing each vector, but I think it would be simpler to use ListVectorPlot.

Answer

I imported your data

data = Import["http://pastebin.com/download.php?i=VByC3ZEg", "Table"];

and transformed it into a vector field, deleting duplicated entries:

vecdata = Partition[#, 3] & /@ DeleteDuplicates[data];

As noted in a comment, the base points all lie in the xy-plane (and the z-components of the vectors are nearly the same):

vecdata[[All, 1, 3]] // Union

{0.}

vecdata[[All, 2, 3]] // Union

{-1., -0.998891, -0.995571, -0.990063, -0.982406}

Since the points lie in a plane, ListVectorPlot3D cannot interpolate a vector field over a region in space and plot it. I can suggest two different visualizations, plotting the vectors themselves (as you considered) and projecting the vectors onto the plane and plotting that field.

The 3D vectors:

Graphics3D[{ColorData[1][1], Arrowheads[Medium], Arrow[{First@#, Total@#}] & /@ vecdata}]

3D plot of vectors

2D ListVectorPlot:

ListVectorPlot[Map[Most, vecdata, {2}]]

2D ListVectorPlot

Comments

plotting - Filling between two spheres in SphericalPlot3D

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plotting - Plot 4D data with color as 4th dimension

I have a list of 4D data (x position, y position, amplitude, wavelength). I want to plot x, y, and amplitude on a 3D plot and have the color of the points correspond to the wavelength. I have seen many examples using functions to define color but my wavelength cannot be expressed by an analytic function. Is there a simple way to do this? Answer Here a another possible way to visualize 4D data: data = Flatten[Table[{x, y, x^2 + y^2, Sin[x - y]}, {x, -Pi, Pi,Pi/10}, {y,-Pi,Pi, Pi/10}], 1]; You can use the function Point along with VertexColors . Now the points are places using the first three elements and the color is determined by the fourth. In this case I used Hue, but you can use whatever you prefer. Graphics3D[ Point[data[[All, 1 ;; 3]], VertexColors -> Hue /@ data[[All, 4]]], Axes -> True, BoxRatios -> {1, 1, 1/GoldenRatio}]

plotting - Adding a thick curve to a regionplot

Suppose we have the following simple RegionPlot: f[x_] := 1 - x^2 g[x_] := 1 - 0.5 x^2 RegionPlot[{y < f[x], f[x] < y < g[x], y > g[x]}, {x, 0, 2}, {y, 0, 2}] Now I'm trying to change the curve defined by $y=g[x]$ into a thick black curve, while leaving all other boundaries in the plot unchanged. I've tried adding the region $y=g[x]$ and playing with the plotstyle, which didn't work, and I've tried BoundaryStyle, which changed all the boundaries in the plot. Now I'm kinda out of ideas... Any help would be appreciated! Answer With f[x_] := 1 - x^2 g[x_] := 1 - 0.5 x^2 You can use Epilog to add the thick line: RegionPlot[{y < f[x], f[x] < y < g[x], y > g[x]}, {x, 0, 2}, {y, 0, 2}, PlotPoints -> 50, Epilog -> (Plot[g[x], {x, 0, 2}, PlotStyle -> {Black, Thick}][[1]]), PlotStyle -> {Directive[Yellow, Opacity[0.4]], Directive[Pink, Opacity[0.4]],

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