Transformations, flows, and Arnold's cat

  Some linear transformations

[Graphics:HTMLFiles/kitty2_1.gif]

(3    )                  horizontal expansion  -  2   0     0   1

[Graphics:HTMLFiles/kitty2_3.gif]

(1    )                  dilation    -  2   0       1      -  0   2

[Graphics:HTMLFiles/kitty2_5.gif]

(3      )                 degenerate    -  2    1         2       --  -1    3

[Graphics:HTMLFiles/kitty2_7.gif]

(    3)                   horizontal shear      -  1   2     0   1

[Graphics:HTMLFiles/kitty2_9.gif]

(1          Sqrt[3] )           rotation&nbs ... bsp; (by π/3)  -          -------  2             2    Sqrt[3]   1  --------   -      2      2

[Graphics:HTMLFiles/kitty2_11.gif]

(1    0 )            reflection     0    -1

[Graphics:HTMLFiles/kitty2_13.gif]

kittynl[m_, options___] := Show[ParametricPlot[Evaluate[m[#1], Prepend[π/4#2, t]], Displa ...    AspectRatio -> 1, Axes -> False, PlotRange -> 2 {{-1, 1}, {-1, 1}}, options]

Show[kittynl[#&], DisplayFunction $DisplayFunction]

[Graphics:HTMLFiles/kitty2_16.gif]

⁃Graphics⁃

kittynl[# + .25 {#〚1〛^2, #〚2〛 - #〚1〛} &, DisplayFunction $DisplayFunction]

[Graphics:HTMLFiles/kitty2_19.gif]

⁃Graphics⁃

f1[t_][{x_, y_}] := {x + t x^2, y + t (y - x)}/(1 + t^2)

kittynl[f1[#/10]] &/@Range[0, 7]

{⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃}

Show[GraphicsArray[Partition[%, 4]]]

[Graphics:HTMLFiles/kitty2_25.gif]

⁃GraphicsArray⁃

kittym[m_, options___] := kittynl[m . #&, options]

<<Graphics`Arrow`

transf[m_, options___] := Show[GraphicsArray[{Graphics[{{GrayLevel[.5], Arrow[{0, 0}, m . {1,  ...  0}, m . {0, 1}]}, AspectRatio->1, PlotRange -> 2 {{-1, 1}, {-1, 1}}], kittym[m, options]}]]

transf[MatrixExp[.1 {{0, 1}, {-1, 0}}]]

[Graphics:HTMLFiles/kitty2_31.gif]

⁃GraphicsArray⁃

Eigenvalues[{{-1, 2}, {3, 2}}]//N

RowBox[{{, RowBox[{RowBox[{-, 2.37228}], ,, 3.37228}], }}]

Det[MatrixExp[#/25 {{-1, 2}, {3, 2}}]] &/@Range[0, 7]//N

RowBox[{{, RowBox[{1., ,, 1.04081, ,, 1.08329, ,, 1.1275, ,, 1.17351, ,, 1.2214, ,, 1.27125, ,, 1.32313}], }}]

kittym[MatrixExp[#/25 {{-1, 2}, {3, 2}}]] &/@Range[0, 7]

{⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃}

Show[GraphicsArray[Partition[%, 4]]]

[Graphics:HTMLFiles/kitty2_40.gif]

⁃GraphicsArray⁃

Det[MatrixExp[# {{-.1, 0}, {0, .1}}]] &/@Range[0, 7]

RowBox[{{, RowBox[{1, ,, 1., ,, 1., ,, 1., ,, 1., ,, 1., ,, 1., ,, 1.}], }}]

kittym[MatrixExp[# {{-.1, 0}, {0, .1}}]] &/@Range[0, 7]

{⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃}

Show[GraphicsArray[Partition[%, 4]]]

[Graphics:HTMLFiles/kitty2_47.gif]

⁃GraphicsArray⁃

Det[MatrixExp[# {{0, .25}, {0, 0}}]] &/@Range[0, 7]

RowBox[{{, RowBox[{1, ,, 1., ,, 1., ,, 1., ,, 1., ,, 1., ,, 1., ,, 1.}], }}]

kittym[MatrixExp[# {{0, .25}, {0, 0}}]] &/@Range[0, 7]

{⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃}

Show[GraphicsArray[Partition[%, 4]]]

[Graphics:HTMLFiles/kitty2_54.gif]

⁃GraphicsArray⁃

kittym[MatrixExp[# {{-.4, .5}, {-.5, .3}}]] &/@Range[0, 19]

{⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃ ... ;, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃, ⁃Graphics⁃}

Show[GraphicsArray[Partition[%, 4]]]

[Graphics:HTMLFiles/kitty2_59.gif]

⁃GraphicsArray⁃


Created by Mathematica  (November 14, 2003)