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How to assign special colors to the output of DensityPlot?

GROUPS:
I have created the following function for plotting
plotDynamical[iterMethod_, points_] :=
DensityPlot[
  iterAlgorithm, {t, xxMin, xxMax}, {s, yyMin,yyMax},
  PlotRange -> {1,4}, ColorFunction -> {Orange, Blue, Black, Green},
  PlotPoints -> points]

The possible results of " iterAlgorithm " are 1 , 2, 3 or 4. I would like to assigning colours to numbers like so: Orange to 1,Blue to 2,Black to 3 and Green to 4. How can I do this?
And complete Algorithm is:
 
 F = Compile[{{t, _Real}, {s, _Real}}, {t^2 + s^2 - 4, -Exp[t] + s -
      1}];
 dF = Compile[{{t, _Real}, {s, _Real}}, {{2 t, 2 s}, {-E^t, 1}}];
 invdF = Compile[{{t, _Real}, {s, _Real}}, {{1/(
      2 E^t s + 2 t), -((2 s)/(2 E^t s + 2 t))}, {E^t/(
      2 E^t s + 2 t), (2 t)/(2 E^t s + 2 t)}}];
 
 rootF[1] = {-1.59832066552612835, 1.202235854627582} ;
rootF[2] = {0, 2} ;


rootPosition =
Compile[{{t, _Real}, {s, _Real}},
  Which[Norm[{t, s} - rootF[1]] < 10.0^(-10), 3,
   Norm[{t, s} - rootF[2]] < 10.0^(-10), 2, True,
   1], {{rootF[_, _], _Real, _Real}}];

iterPsM10 = Compile[{{t, _Real}, {s, _Real}},
  Block[{v = F[t, s], w = dF[t, s], u = invdF[t, s], x, y, z, dFz, Q,
    uu, vv, Fu, vu, invdFvu},
   x = {t, s};
   y = x - (1/2 ) u.v;
   z = 1/3 (4 y - x);
   dFz = dF @@ ({z[[1]], z[[2]]});
   Q = Inverse[w - 3 dFz];
   uu = y + Q.v;
   Fu = F @@ ({uu[[1]], uu[[2]]});
   vv = uu + 2 Q.Fu;
   vu = 1/2 (vv + uu);
   invdFvu = invdF @@ ({vu[[1]], vu[[2]]});
   uu - invdFvu.Fu]];

iterAlgorithm[iterMethod_, lim_] :=
Block[{ct, r}, ct = 0; r = rootPosition[t, s];
  While[(r == 1) && (ct < lim), ++ct; {t, s} = iterMethod[t, s];
   r = rootPosition[t, s]];
  If[Head[r] == Which, r = 0];(*"Which" unevaluated*)Return[r]];

limIterations = 1000;
xxMin = -5; xxMax = 5; yyMin = -5; yyMax = 5;

plotDynamical[iterMethod_, points_] :=
DensityPlot[iterAlgorithm[iterMethod, limIterations],
  {t, xxMin, xxMax}, {s, yyMin, yyMax}, PlotRange -> {0, 3},
  ColorFunction -> {Green, Black, Orange, Blue},
  PlotPoints -> points,
  Epilog -> {White, PointSize[.02], Point[rootF[1]], Point[rootF[2]]}];


plotDynamical[iterPsM10, 56]
Attachment

Attachments:
POSTED BY: Qasem Marzei
Answer
5 months ago

How to assign special colors to the output of DensityPlot?

POSTED BY: Qasem Marzei
Answer
4 months ago

Dear Qasem,

Try using ArrayPlot:

ArrayPlot[{{1, 0, 0, 0.3}, {1, 1, 0, 0.3}, {1, 0, 1, 0.7}}, ColorRules -> {1 -> Pink, 0 -> Yellow}]

Here you can assign certain values to certain colors.

POSTED BY: Sander Huisman
Answer
4 months ago

DensityPlot like all graphics take option ColorFunction, which could be a pretty arbitrary function:

DensityPlot[y + Sin[x^2 + 3 y], {x, -3, 3}, {y, -3, 3}, ColorFunction -> (RGBColor[1 - #, #, 1] &)]

You can make up the function you need.

POSTED BY: Sam Carrettie
Answer
4 months ago

How to assign special colors to the output of DensityPlot?

POSTED BY: Qasem Marzei
Answer
3 months ago

Can anyone help me ?

POSTED BY: Qasem Marzei
Answer
1 month ago