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Topic: Re: {mg4240] Plot and colors
Replies: 0

 Jens-Peer Kuska Posts: 12 Registered: 12/7/04
Re: {mg4240] Plot and colors
Posted: Jun 28, 1996 9:53 AM

here is the principle solution.

Needs["Utilities`FilterOptions`"]

Options[ColorPlot]:=
{ColorFunction ->Hue,Axes->True}

ColorPlot[f_,{x_,x0_,xe_},opt___]:=
Module[{gr,cfun},
cfun=ColorFunction /. {opt} /. Options[ColorPlot];
gr=First[
Plot[
f,{x,x0,xe},
DisplayFunction->
Identity
]
] //. Line[{a_,b_,c__}] :>
Sequence @@ {Line[{a,b}],
Line[{b,c}]} /.
Line[{a_,b_}] :>
{cfun[Last[a+b]],Line[{a,b}]};
Show[
Graphics[
gr,
Sequence @@
{FilterOptions[Graphics,opt],
FilterOptions[Graphics,Sequence @@ Options[Plot]]}
]
]
]

Now

ColorPlot[Sin[x],{x,0,Pi}]

works. You may set the desired color function with the option ColorFunction.
A rescaling to the maximum/min range may be usefull, but this is a quick
and dirty solution. Here the explanation. Plot generates one line with
all points of the curve, to color the different line segments one must split
the one long line into a list of lines connecting only two points, the
replacement Line[{a_,b_,c__}] :> .. does this. Than one has to add the color
information for every line segment by replacing every line segment by a color
directive due to the ave y-value and the original line information. In the last
step a graphics object is created with the options of Plot ( axes ..).

Hope that helps

Jens