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I tried to plot the following curves in Mathematica using "ListContourPlot" , and compared them with the results from Matlab 2019a.

Mathematica code: (cite from Reference (1))

meshgrid[x_List, y_List] := {ConstantArray[x, Length[x]], 
  Transpose@ConstantArray[y, Length[y]]}

{xx, yy} = meshgrid[Range[-2, 2, 0.1], Range[-4, 4, 0.2]];
c = xx*Exp[-xx^2 - yy^2];

pts = Flatten[{xx, yy, c}, {2, 3}];

ListContourPlot[pts]

Mathematica results

Matlab code:

x = linspace(-2,2,40);
y = linspace(-4,4,40);
[X,Y] = meshgrid(x,y);
Z = X .* exp(-X.^2 - Y.^2);
contourf(X,Y,Z,10)

Matlab results

The plotting effects from both softwares are not the same.

My question is how can we have the ContourPlot effects (this example) like those in Matlab?

References:

(1). Simulate MATLAB's meshgrid function

(2). Filled 2-D contour plot

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  • 1
    $\begingroup$ how about ListContourPlot[pts, PlotRange -> All, Contours -> 10, ColorFunction -> "BlueGreenYellow"]? $\endgroup$
    – kglr
    May 28, 2021 at 0:28
  • $\begingroup$ @kglr this methd is not good, because two eclipses are too small... $\endgroup$
    – ABCDEMMM
    May 28, 2021 at 0:33
  • 1
    $\begingroup$ try also the option Contours -> DeleteCases[0][Subdivide[-3, 3, 10]/10]? $\endgroup$
    – kglr
    May 28, 2021 at 0:44
  • $\begingroup$ @kglr thanks a lot for your suggestion, it is imporved, but the external circles are still too small, you may take a look at the matlab plot results. $\endgroup$
    – ABCDEMMM
    May 28, 2021 at 0:46
  • $\begingroup$ @ABCDEMMM ListContourPlot[pts, PlotRange -> All, Contours -> DeleteCases[0][Subdivide[-3, 3, 10]/10], ColorFunction -> "BlueGreenYellow", AspectRatio -> 1/GoldenRatio] $\endgroup$
    – cvgmt
    May 28, 2021 at 2:00

1 Answer 1

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I guess this is something you want to get:

scaling = 0.80;
ListContourPlot[
  pts,
  PlotRange -> All,
  ColorFunction -> "BlueGreenYellow",
  Contours -> Subdivide[scaling Min[Last /@ pts], scaling Max[Last /@ pts], 9],
  AspectRatio -> 0.8
]

enter image description here

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  • $\begingroup$ in addition, is there a mathematica command like "meshgrid" in matlab? $\endgroup$
    – ABCDEMMM
    May 28, 2021 at 3:00
  • 1
    $\begingroup$ @ABCDEMMM Are you looking for Outer[List, array1, array2] or CoordinateBoundsArray? $\endgroup$
    – b3m2a1
    May 28, 2021 at 3:06
  • $\begingroup$ @b3m2a1 I got the point that you mean for this question! thanks! $\endgroup$
    – ABCDEMMM
    May 28, 2021 at 3:08
  • $\begingroup$ Is there a mathematica command like "meshgrid" in matlab? ClearAll["Global*"] meshgrid[x_List, y_List] := {ConstantArray[x, Length[x]], Transpose@ConstantArray[y, Length[y]]} {xx, yy} = meshgrid[Range[-2, 2, 0.1], Range[-4, 4, 0.2]]; c = xx*Exp[-xx^2 - yy^2]; pts = Flatten[{xx, yy, c}, {2, 3}]; Using CoordinateBoundsArray` grid = Transpose@CoordinateBoundsArray[{{-2, 2}, {-4, 4}}, {0.1, 0.2}]; c1 = Apply[#1 Exp[-#1^2 - #2^2] &, grid, {2}]; pts1 = Flatten /@ Flatten[{grid, c1}, {2, 3}]; Using Outer grid2 = Transpose@Outer[List, Range[-2, 2, 0.1], Range[-4, 4, 0.2]]; c2 = Apply[#1 Exp[-# $\endgroup$ May 28, 2021 at 4:05
  • $\begingroup$ how to automatically find the scaling value? $\endgroup$
    – ABCDEMMM
    May 28, 2021 at 4:18

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