MathGroup Archive 2002

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Questions on Plot

  • To: mathgroup at
  • Subject: [mg36771] Re: [mg36752] Questions on Plot
  • From: Omega Consulting <omega_consulting at>
  • Date: Tue, 24 Sep 2002 01:34:26 -0400 (EDT)
  • Sender: owner-wri-mathgroup at

At 03:32 AM 9/22/2002, Steve Gray wrote:
>I would appreciate help with these problems:
>1. I'm plotting several thousand points, which I can do
>either with something like this (this is a test):
>w = Table[Point[{Random[], Random[]}], {i, 1, 4096}];
>x = Table[Point[{Random[], Random[]}], {i, 1, 4096}];
>y = Table[Point[{Random[], Random[]}], {i, 1, 4096}];
>z = Table[Point[{Random[], Random[]}], {i, 1, 4096}];
>dw = Graphics[{PointSize[0.01], RGBColor[ 1, 0, 0], w}];
>dx = Graphics[{PointSize[0.01], RGBColor[.8, .8, .8], x}];
>dy = Graphics[{PointSize[0.01], RGBColor[ 0, .5, .9], y}];
>dz = Graphics[{PointSize[0.01], RGBColor[.8, .8, 0], z}];
>Show[dw, dx, dy, dz, AspectRatio -> Automatic,
>    PlotRange -> {{0, 1}, {0, 1}},
>             Axes -> Automatic,
>             Frame -> True,
>    Background -> GrayLevel[.026],
>    GridLines -> Automatic];
>This gives me dots in 4 colors for distinguishing different
>kinds of points in my real application. This works fine but
>needs the Point structure. Or, I can do (this is for one
>kind of point),
>t = Table[{Random[], Random[]}, {i, 1, 1024}];
>ListPlot[t, AspectRatio -> Automatic,
>             Axes -> Automatic,
>             Frame -> True,
>    Background -> GrayLevel[.026]
>    ];
>which seems simpler and may fit into the rest of the program
>more easily.
>1. How do I get the RGBColor Rule or the equivalent into
>the latter? The RGBColor[] call is not a rule.
>2. In the latter case I also want to plot 4 types of points.
>How do I get ListPlot to put down 4 plots superimposed?
>Or can't I?
>3. In either case, I need to make the whole plot area about
>twice as big. That is, it now occupies about a 4" square. To
>see details better in my real plot, and because with 16k points
>the small plot just looks almost like a solid blur, I want to
>make it more like 8" square, or as big as will fit the screen
>(without changing the plot range or anything else). There
>must be a scale factor somewhere.
>Thank you for any information.

You can plot more than one list with MultipleListPlot.


If you don't like the default symbols used by MultipleListPlot, then you 
can create your own.

ColorPoint[color_] := MakeSymbol[{color,Point[{0,0}]}]

Create the data.

z= Table[{Random[],Random[]},{i,1,1024}];

And plot

       ColorPoint[RGBColor[.8, .8, .8]],ColorPoint[RGBColor[ 0, .5, .9]],
       ColorPoint[RGBColor[.8, .8, 0]]},

Omega Consulting
"The final answer to your Mathematica needs"

Spend less time searching and more time finding.

  • Prev by Date: Re: List operation, LabeledListPlot, Goto Statement
  • Next by Date: Strange ReplaceAll behavior
  • Previous by thread: RE: Questions on Plot
  • Next by thread: Defining Multiple Forms of a Function for Different Purposes