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plotting - How does one set a logarithmic scale in a ContourPlot?


How does one set a logarithmic scale for both x and y axes in ContourPlot in Mathematica?




Answer



One possibility is to plot the contour plot with linear scales using ContourPlot and use ListLogLogPlot to transform this plot to one with logarithmic scales:


pl = Normal@
  ContourPlot[
   Sin[3 x] + Cos[3 y] == 1/2, {x, .01 Pi, 3 Pi}, {y, .01 Pi, 3 Pi}, 
   PlotPoints -> 30]

Mathematica graphics


ListLogLogPlot[Cases[pl, Line[a_, b___] :> a, Infinity], 
 Joined -> True, Frame -> True, PlotRange -> All, AspectRatio -> 1, 

 PlotStyle -> ColorData[1][1]]

Mathematica graphics


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