Re: ListPlot - assigning a list of colors to a set of points

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• Subject: [mg131964] Re: ListPlot - assigning a list of colors to a set of points
• From: Bob Hanlon <hanlonr357 at gmail.com>
• Date: Wed, 6 Nov 2013 00:38:24 -0500 (EST)
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```Make each point a separate data list and repeat the PointSize:

ListPlot[List /@ {{1, 1}, {2, 2}, {3, 3}},
PlotStyle -> (Directive[PointSize[0.02], #] & /@
{Red, Green, Blue})]

Although you can use a List instead of Directive:

ListPlot[List /@ {{1, 1}, {2, 2}, {3, 3}},
PlotStyle -> ({PointSize[0.02], #} & /@
{Red, Green, Blue})]

Alternatively,

ListPlot[List /@ {{1, 1}, {2, 2}, {3, 3}},
PlotStyle -> {Red, Green, Blue},
PlotMarkers -> {Automatic, Medium}]

Bob Hanlon

On Mon, Nov 4, 2013 at 11:16 PM, Gordon Robertson <grobertson at bcgsc.ca>wrote:

>
> I'm using Mathematica v9.x on a Mac, with OS X 10.7.5.
>
> Could I ask about something that likely has a very simple solution? I have
> a list of XY coordinates for say 500 points that will become a scatterplot
> via ListPlot. I need to assign a colour to each point, using a list of
> labels (histology, risk, =85).
>
> I've generated ArrayPlot graphics for cases like this for some time. For
> example, given some labels in column 4 of a 'hist' table:
> colours = Table[{
>     Switch[name = hist[[i, 4]],
>      "Classical", Green, "Tall cell", Red, "Other", Blue]
>     }, {i, Length[hist]}];
>  ArrayPlot[{colours}, AspectRatio -> 0.1, Frame -> False]
>
> For a ListPlot, I'd have thought that something as simple as dropping a
> list of colours into a PlotStyle Directive would do the job. But the
> following line plots three blue points, rather than a Red, Green and Blue
> point.
> ListPlot[{{1, 1}, {2, 2}, {3, 3}},
>  PlotStyle -> Directive[PointSize[0.02], {Red, Green, Blue}]]
>
> Is there a simple way to declare a list of colours in ListPlot? I've
> looked through the PlotStyle documentation, and apologize if I've missed
> seeing how to do this.
>
> Thanks very much for your help.
>
> Gordon
> --
> Gordon Robertson
> Michael Smith Genome Sciences Centre
> BC Cancer Agency