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Possible Slowdown in v11.1

I have a DensityPlot and ContourPlot I would like to speed up in V11.1.1. Is there any way to achieve a speed up in the following examples? Perhaps through parallelization or compilation? 

AbsoluteTiming[
ContourPlot[
      Mod[Floor[-5 Im[Log[Log[Sin[Sin[x - I y] + Sin[y + I x]]]]]], 40], 
      {x, -3, 3}, {y, -3, 3}, 
      ContourLines -> False, Frame -> False, Background -> Black, 
      ColorFunction -> (RGBColor[1 - #^1.5, Abs[Sin[2 \[Pi] #]], 
         4 #^2 - 2 # + 3] &), 
      PlotPoints -> 200, Contours -> 45, 
      PerformanceGoal -> "Speed", 
      ContourLabels -> None]
]
(* takes over 20 mins *)

enter image description here

AbsoluteTiming[
   DensityPlot[
   Length[FixedPointList[(# - (Cos[#] + #^2/2)/(-Sin[#] + #)) &, 
     x + I y, 10, SameTest -> (Abs[#1 - #2] < 10^-10 &)]], {x, 5, 
    7}, {y, -4, -3}, Mesh -> False, AspectRatio -> Automatic, 
   Frame -> False, Axes -> False, 
   PlotPoints -> 200, PerformanceGoal -> "Speed",
   ColorFunction -> (If[# >= 1, RGBColor[0, 0, 0], Hue[1 - 2 #]] &)]]

(* takes over 20 mins *)

enter image description here

Note: part of the problem is that I'd like need to the resolution high by fixing the options PlotPoints and Contours.

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7
  • $\begingroup$ the both take only seconds for me ( first one ~5 sec second one less than 1 second. ) $\endgroup$
    – george2079
    Jun 9, 2017 at 18:44
  • $\begingroup$ @george2079 are you on a supercomputer? that's not possible, can you post the output? $\endgroup$
    – M.R.
    Jun 9, 2017 at 18:47
  • $\begingroup$ I stuck my images in the post.. computer is 3GHz / 32Gb. BTW I tried running without the Speed performance goal and that was taking a long time. $\endgroup$
    – george2079
    Jun 9, 2017 at 19:04
  • $\begingroup$ @george2079 Thanks, and what version of MMA do you have, what are your exact timings? $\endgroup$
    – M.R.
    Jun 9, 2017 at 19:28
  • $\begingroup$ I think most users only have 2.5 GHz/16Gb at most. $\endgroup$
    – M.R.
    Jun 9, 2017 at 19:38

1 Answer 1

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This is I think a better way to do that first plot. The function actually returns only 40 discrete integer values (Which I think is giving ContourPlot issues ) so you are better off to essentially generate a raster image.

(dat = Table[
     Mod[Floor[-5 Im[Log[Log[Sin[Sin[x - I y] + Sin[y + I x]]]]]], 
       40] /. y -> 1, {x, -3, 3, 6/500}, 
      {y, -3, 3, 6/500}]); // AbsoluteTiming

385.829

ArrayPlot[dat, ColorFunction -> "Rainbow"]

enter image description here

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