How to set PlotLegend Number Format

Question

Is there any way to make Mathematica to show the legend labels like a real number rather than in fraction form? I read the BarLegend options, however they are just related to graphics so I just set the PlotLegend to Automatic.

A sample of legend I have problem with is shown below:

MatrixPlot[Rm1,
 ColorFunction -> ColorData["GrayTones"],
 ImageSize -> 200,
 PlotLegends -> Automatic]

enter image description here

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score 2 · Answer 1 · answered Apr 05 '13 at 03:33

2

This should do it:

plot = MatrixPlot[Rm1, ColorFunction -> ColorData["GrayTones"],
   ImageSize -> 200, PlotLegends -> Automatic];
MapAt[N, plot, 2]

enter image description here

answered Apr 05 '13 at 03:33

Brett Champion

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ha ha! simple and effective! Thanks Brett. – K-1 Apr 06 '13 at 09:09

xslittlegrass · Answer 2 · 2014-09-18T17:00:47.803

You can also do this way:

plot = MatrixPlot[RandomReal[{0, 1}, {10, 10}], 
  ColorFunction -> ColorData["GrayTones"], ImageSize -> 200, 
  PlotLegends -> Automatic];
plot /. Rational[x_, y_] :> ScientificForm[N[x/y]]

enter image description here

Or combine it with Brett's answer so that it works both for large and small numbers:

plot = MatrixPlot[100000000 RandomReal[{0, 1}, {10, 10}], 
   ColorFunction -> ColorData["GrayTones"], ImageSize -> 200, 
   PlotLegends -> Automatic];
MapAt[N, plot /. Rational[x_, y_] :> ScientificForm[N[x/y]], 2]

enter image description here

plot = MatrixPlot[0.00000001 RandomReal[{0, 1}, {10, 10}], 
   ColorFunction -> ColorData["GrayTones"], ImageSize -> 200, 
   PlotLegends -> Automatic];

MapAt[N, plot /. Rational[x_, y_] :> ScientificForm[N[x/y]], 2]

enter image description here

How to set PlotLegend Number Format

2 Answers2

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