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  • A natural sequence of Herman rings Julias

    From Roger Bagula@21:1/5 to All on Thu Jul 20 08:14:50 2017
    A sequence of Herman rings Julias based on Pisot Polynomial that are minimal or near minimal:

    http://mathworld.wolfram.com/PisotNumber.html

    1) f[z_]=(0.737369+0.67549 I)*z^2*(z^2-z-1)/(-z^2-z+1);
    2) f[z_]=(0.737369+0.67549 I)z^2(z^3-z-1)/(-z^3-z^2+1);
    3) f[z_]+(0.737369+0.67549 I)z^2(z^3-z^2-1)/(-z^3-z+1)
    4) f[z_]=N[Exp[I*2*Pi*1.38028]]*z^2*(z^4-z^3-1)/(-z^4-z+1)
    5) f[z_]=N[Exp[I*2*Pi*1.44327]]*z^2*(z^5-z^4-z^3+z^2-1)/(-z^5+z^3-z^2-z+1);

    Links to pictures at Google+: ( I hope the links work)
    1) https://plus.google.com/photos/photo/110803890168343196795/6444864197749190994?icm=false&authkey=CMve54qiz_fb7AE&sqid=109460294103647789464&ssid=418526d2-c6d4-4dda-975d-30c70d0dd7d3

    2) https://lh3.googleusercontent.com/-2BWlejRrcJw/WW-RxGeknUI/AAAAAAABWG8/wYCb7DFzF58fuOlyKByuS2Em3ctaFz6rQCJoC/w530-h529-p/Herman_ring_Bicritical_Dianalytic_minimalpisot_33_Argmon.png

    3) https://lh3.googleusercontent.com/-2BWlejRrcJw/WW-RxGeknUI/AAAAAAABWG8/wYCb7DFzF58fuOlyKByuS2Em3ctaFz6rQCJoC/w530-h529-p/Herman_ring_Bicritical_Dianalytic_minimalpisot_33_Argmon.png

    4) https://plus.google.com/photos/110803890168343196795/album/6444854399483671873/6444854401281344594?authkey=CJnt5JmwjJahKg&sqid=109460294103647789464&ssid=418526d2-c6d4-4dda-975d-30c70d0dd7d3

    5) https://plus.google.com/photos/110803890168343196795/album/6444859387499272257/6444859387218089266?authkey=CNva1ay7vc-TywE&sqid=109460294103647789464&ssid=418526d2-c6d4-4dda-975d-30c70d0dd7d3

    Mathematica program:
    (* Mathematica*)
    toRGBs[h_] :=
    If[h >= 0.,(*Color function*)List @@ Blend["ThermometerColors", h](*outside*),
    List @@ Blend["CMYKColors", -h]] (*inside*);

    wrongbrot =
    Compile[{{x, _Real}, {y, _Real}},
    Module[{ct = 0, t, c = x + y I, z = x + y I, min = 10., count = 0},
    While[Abs[z] < 32 && ct++ <= 32^2,
    z = (0.737369 + 0.67549 I)*z^2*(z^3 - z - 1)/(-z^3 - z^2 + 1);
    If[Abs[z] < min, min = Abs[z]; count = ct]];
    If[ct <= 200,
    Mod[Abs[Arg[x + I*y]]/(2*Pi)*Log[ct + 1],
    1], -Mod[Abs[Arg[x + I*y]/(4*Pi)]*count*Sqrt[8.], 1.]]]];
    center = {-0.5, .0}; size = {3., 3.};
    xres = 1501; dx = dy = 2*size[[1]]/(xres - 1);
    {{xl, yl}, {xh, yh}} = {{-1.5001, -1.8}, {2.1, 1.8}};
    cols = Table[
    toRGBs[Log[1 + wrongbrot[x, y]]], {y, yl, yh, dy}, {x, xl, xh, dx}];
    g = Graphics[Raster[cols], ImageSize -> 1500]

    (*end*)

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Roger Bagula@21:1/5 to All on Thu Jul 20 09:11:00 2017
    The heptic (x^7) version gives an Herman rings Julia in the sequence:
    NSolve[-1 + x^2 - x^5 - x^6 + x^7 == 0, x]

    {{x -> -0.868706 - 0.239062 I}, {x -> -0.868706 +
    0.239062 I}, {x -> -0.212614 - 0.953977 I}, {x -> -0.212614 +
    0.953977 I}, {x -> 0.808713 - 0.424846 I}, {x ->
    0.808713 + 0.424846 I}, {x -> 1.54522}}

    p[x_] = -1 + x^2 - x^5 - x^6 + x^7



    q[x_] = ExpandAll[x^7*p[1/x]]

    1 - x - x^2 + x^5 - x^7

    f[z_]=N[Exp[I*2*Pi*1.54522]]*z^2*(p[z])/(q[z]);

    https://plus.google.com/photos/110803890168343196795/album/6444885899096501329/6444885901731328482?authkey=CNCNn-O8obv7lAE&sqid=109460294103647789464&ssid=418526d2-c6d4-4dda-975d-30c70d0dd7d3

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Roger Bagula@21:1/5 to All on Thu Jul 20 13:34:30 2017
    Some more of the minimal Pisot types beyond the pentic:

    (* Mathematica: sequence of minimal Pisots and near minimal Pisots*)
    Clear[p, \
    q]
    (* list of probable minimal Pisot polynomials*)
    p = {-1, x - 1, x^2 - x - 1,
    x^3 - x - 1,
    x^4 - x^3 - 1, -1 + x^2 - x^3 - x^4 + x^5, -1 + x^2 - x^4 - x^5 + x^6, -1 +
    x^2 - x^5 - x^6 + x^7, -1 + x^2 - x^6 - x^7 + x^8, -1 + x^2 - x^7 - x^8 +
    x^9, -1 + x^2 - x^8 - x^9 + x^10, -1 + x^2 - x^9 - x^10 + x^11, -1 + x^2 -
    x^10 - x^11 + x^12, -1 + x^2 - x^11 - x^12 + x^13, -1 + x^2 - x^12 - x^13 +
    x^14, -1 + x^2 - x^13 - x^14 + x^15, -1 + x^2 - x^14 - x^15 + x^16, -1 +
    x^2 - x^15 - x^16 + x^17, -1 + x^2 - x^16 - x^17 + x^18, -1 + x^2 - x^17 -
    x^18 + x^19, -1 + x^2 - x^18 - x^19 + x^20}
    Clear[q]
    q[x_, i_] := ExpandAll[x^(i - 1)*(p[[i]] /. x -> 1/x)] TableForm[Table[CoefficientList[p[[i]], x], {i, Length[p]}]]
    Table[Apply[Plus, CoefficientList[p[[i]], x]], {i, Length[p]}] TableForm[Table[CoefficientList[Expand[q[x, i]], x], {i, Length[p]}]]
    aa = Table[{Re[x], Im[x]} /. NSolve[p[[i]] == 0, x], {i, 2, Length[p]}] ListPlot[Flatten[aa, 1], PlotStyle -> Red]
    (* end*)
    (*Mathematica*)
    p8 = x /. NSolve[-1 + x^2 - x^6 - x^7 + x^8 == 0, x][[8]]
    p[x_] = -1 + x^2 - x^6 - x^7 + x^8
    q[x_] = ExpandAll[x^8*p[1/x]]

    toRGBs[h_] :=
    If[h >= 0.,(*Color function*)List @@ Blend["DarkRainbow", h](*outside*),
    List @@ Blend["CMYKColors", -h]] (*inside*);

    wrongbrot =
    Compile[{{x, _Real}, {y, _Real}},
    Module[{ct = 0, t, c = x + y I, z = x + y I, min = 10., count = 0},
    While[Abs[z] < 32 && ct++ <= 32^2, z = N[Exp[I*2*Pi*p8]]*z^2*p[z]/q[z];
    If[Abs[z] < min, min = Abs[z]; count = ct]];
    If[ct <= 200,
    Mod[Abs[Arg[x + I*y]]/(2*Pi)*Log[ct + 1],
    1], -Mod[Abs[Arg[x + I*y]/(4*Pi)]*count*Sqrt[8.], 1.]]]];
    center = {-0.5, .0}; size = {3., 3.};
    xres = 1501; dx = dy = 2*size[[1]]/(xres - 1);
    {{xl, yl}, {xh, yh}} = {{-1.45001, -1.85}, {2.25, 1.85}};
    cols = Table[
    toRGBs[Log[1 + wrongbrot[x, y]]], {y, yl, yh, dy}, {x, xl, xh, dx}];
    g = Graphics[Raster[cols], ImageSize -> 1500]

    (*end*)

    https://scontent-lax3-1.xx.fbcdn.net/v/t1.0-9/20229347_10155517592961499_2088088800225894885_n.jpg?oh=d3a40318a68e3309237e943b56f44f4c&oe=5A04D46D

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
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