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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


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