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I have the following color table:

colTable = 
  {{Black}, Table[{Blend[{Blue, Green, Yellow, Red}, x]}, {x, 1/2000, 1, 1/2000}]}; 
colTable = Flatten[colTable];

I can color a list plot curve when the plot is joined, but not the plot markers when the plot is not joined.

The following code

plot = ListPlot[coordinates*dx, 
   ColorFunction -> (Blend[colTable, #] &), Joined -> True, 
   Frame -> True, PlotRange -> {{0, 130*dx}, {0, 130*dx}}, 
   PlotStyle -> {RGBColor[0, 0, 1], Thickness[0.002]}, 
   AspectRatio -> 1, 
   FrameLabel -> {{"y in mm", ""}, {"x in mm", imageDir}}, 
   BaseStyle -> {FontWeight -> "Bold", FontSize -> 30, 
     FontFamily -> "Calibri"}, ImageSize -> 2000];

gives

enter image description here

Buy when drawing only the markers with this code

plot = ListPlot[coordinates*dx, 
   ColorFunction -> (Blend[colTable, #] &), Joined -> False, 
   Frame -> True, PlotMarkers -> Automatic, 
   PlotRange -> {{0, 130*dx}, {0, 130*dx}}, 
   PlotStyle -> {RGBColor[0, 0, 1], Thickness[0.002]}, 
   AspectRatio -> 1, 
   FrameLabel -> {{"y in mm", ""}, {"x in mm", imageDir}}, 
   BaseStyle -> {FontWeight -> "Bold", FontSize -> 30, 
     FontFamily -> "Calibri"}, ImageSize -> 2000];

I get:

enter image description here

What am I doing wrong?

With the help example from – J. M.♦ I get now the correct image below for plot markers, when using the following code:

 plot = ListPlot[MapThread[Style, {coordinates*dx, colTable}], 
   PlotStyle -> AbsolutePointSize[15], Frame -> True, 
   PlotRange -> {{0, 130*dx}, {0, 130*dx}}, AspectRatio -> 1, 
   FrameLabel -> {{"y (mm)", ""}, {"x (mm)", imageDir}}, 
   BaseStyle -> {FontWeight -> "Bold", FontSize -> 30, 
     FontFamily -> "Calibri"}, ImageSize -> 2000];

enter image description here

By the way I have used this same color table and superposed corresponding images (I did not mention that the data are center of mass coordinates of circular shaped objects in CMOS images). Here I get the following image which corresponds to the plot with the markers:

enter image description here

Question: The color table is the same for the joined data points (curve, see top plot) and for the plot markers. So I would assume for the curve at top the same color variation. But it is not the case?

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4
  • $\begingroup$ As I see it, you're coloring by the order of the points in the latter diagram, and by their abscissas in the former diagram. I might be able to come up with something, but to help us help you, please provide at least a subset of your data. $\endgroup$
    – J. M.'s persistent exhaustion ♦
    Oct 28, 2015 at 15:08
  • $\begingroup$ I have used DumpSave and saved the variable "data" to tinyurl.com/qceeuds Thanks for looking into the data ... $\endgroup$
    – mrz
    Oct 28, 2015 at 20:33
  • $\begingroup$ Your data is unreadable for me; that may have to do with the fact that we do not have the same OS. I would suggest putting the data into something like pastebin instead. $\endgroup$
    – J. M.'s persistent exhaustion ♦
    Oct 29, 2015 at 13:43
  • $\begingroup$ Can you read that? pastebin.com/6YALzqwM $\endgroup$
    – mrz
    Oct 29, 2015 at 17:21

3 Answers 3

Reset to default
7
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Unfortunately, as noted in the docs for ListPlot[], "ColorFunction requires at least one dataset to be Joined." One can use Style[] instead to color the points, like so:

data = Table[{x, Sin[x]}, {x, 0, π, π/11}];
cols = ColorData["ThermometerColors", "BlendArgument"];

{ListPlot[MapThread[Style, {data, cols}], Background -> Black, 
          PlotStyle -> AbsolutePointSize[4]], 
ListPlot[data, Background -> Black, ColorFunction -> (Blend[cols, #] &),
         Joined -> True, PlotStyle -> AbsoluteThickness[4]]} // GraphicsRow

joined and disconnected

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3
  • $\begingroup$ Your solution is more than twice faster ... only one question/remark: the markers have grey sourrounding if I use white background? I used the following code: plot = ListPlot[MapThread[Style, {coordinates*dx, colTable}], PlotStyle -> AbsolutePointSize[10], Frame -> True, PlotRange -> {{0, 130*dx}, {0, 130*dx}}, AspectRatio -> 1, FrameLabel -> {{"y (mm)", ""}, {"x (mm)", imageDir}}, BaseStyle -> {FontWeight -> "Bold", FontSize -> 30, FontFamily -> "Calibri"}, ImageSize -> 2000]; $\endgroup$
    – mrz
    Oct 28, 2015 at 9:06
  • $\begingroup$ Not having your data, I can't reproduce that. What happens if you remove Background -> Black in my examples? $\endgroup$
    – J. M.'s persistent exhaustion ♦
    Oct 28, 2015 at 9:11
  • $\begingroup$ Now I tried your example data with white background and it looks good ... $\endgroup$
    – mrz
    Oct 28, 2015 at 10:07
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Make each point a separate data set by mapping List onto the data.

n = 36;
data = Table[{x, Sin[x]}, {x, 0, π, π/n}];
colTable = {{Black}, 
    Table[{Blend[{Blue, Green, Yellow, Red}, x]}, {x, 1/n, 1, 1/n}]} // 
   Flatten;

ListPlot[List /@ data, PlotStyle -> colTable]

enter image description here

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1
  • $\begingroup$ Great ... thanks $\endgroup$
    – mrz
    Oct 28, 2015 at 8:54
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Perhaps:

pts = RandomReal[1, {1000, 2}];
ListPlot[pts, ColorFunction -> (Blend[colTable, #] &), Joined -> True,
   Frame -> True] /. Line[x__] :> {PointSize[0.02], Point[x]}

enter image description here

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