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Is it possible to display e.g., $z=x^2+y^2$ with Plot3D and in the same box, in the $z=0$ plane, plot its gradient?


marked as duplicate by Sjoerd C. de Vries, xzczd, Öskå, Jens, Dr. belisarius plotting Dec 25 '14 at 13:00

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p = Plot3D[x^2 + y^2, {x, -1, 1}, {y, -1, 1}];
pv = VectorPlot3D[{{2 x, 2 y, 0}, {-2 y, 2 x, 0}}, {x, -1, 1}, {y, -1,
     1}, {z, -0.01, 0.01}, 
   PlotRange -> {Automatic, Automatic, {-1, 1}}];
Show[pv, p]

enter image description here


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