Tikz – esempio 17

Benvenuti nel nostro esempio 17 di utilizzo del pacchetto Tikz, una risorsa utilissima del linguaggio per comporre immagini di altissima qualità. In questo articolo proponiamo un esempio di utilizzo. Segnaliamo anche il precedente Tikz – esempio 16 e il successivo Tikz – esempio 18 per ulteriore materiale.

Buona lettura!

 

Prima di ogni figura ricordare di mettere

\documentclass[usenames,dvipsnames]{article}
\usepackage{pgfplots}

Figura 1

codice prima figura

\begin{tikzpicture}
\begin{axis}[
scale=0.8,
axis x line=center,
axis y line=center,
xmin = -2,
xmax = 7.5,
ymin = -1,
ymax = 5,
xlabel = {$\vartheta$},
ylabel = {$\rho$},
xtick = \empty,
ytick = \empty,
axis equal image,
axis on top,
clip = false,
disabledatascaling
]

\addplot[ultra thick,Green,fill=Green!25] coordinates {(0,2) (6.28,2) (6.28,0) (0,0)};
\addplot[ultra thick,red] coordinates {(0,4) (6.28,4) (6.28,0)};
\addplot[very thick, dashed] coordinates {(0,2/3) (6.28,2/3)};
\addplot[very thick, dashed] coordinates {(0,4/3) (6.28,4/3)};
\addplot[very thick, dashed] coordinates {(2,0) (2,4)};
\addplot[very thick, dashed] coordinates {(4,0) (4,4)};
\addplot[ultra thick,OliveGreen,fill=OliveGreen!50] coordinates {(2,2/3) (4,2/3) (4,4/3) (2,4/3)} -- cycle;

\addplot[no marks] coordinates {(0,4)} node[left] {$R$};
\addplot[no marks] coordinates {(0,2/3)} node[left] {$\rho$};
\addplot[no marks] coordinates {(0,4/3)} node[left] {$\rho+\mathrm{d}\rho$};
\addplot[no marks] coordinates {(2,0)} node[below] {$\vartheta$};
\addplot[no marks] coordinates {(4,0)} node[below] {$\vartheta+\mathrm{d}\vartheta$};
\addplot[no marks] coordinates {(3,3)} node {\scalebox{1.5}{$D$}};

\draw[-stealth,ultra thick] (axis cs:7,4) to[bend right=-35] (axis cs:10,4);
\draw[stealth-,ultra thick] (axis cs:7,-1) to[bend right=+35] (axis cs:10,-1);
\addplot[no marks] coordinates {(8.5,5)} node {$\Phi$};
\addplot[no marks] coordinates {(8.5,-2)} node {$\Phi^{-1}$};
\end{axis}

\end{tikzpicture}

seconda figura

codice seconda figura

\begin{tikzpicture}
\begin{axis}[
scale=0.8,
axis x line=center,
axis y line=center,
xmin = 0,
xmax = 5,
ymin = 0,
ymax = 5,
xtick = \empty,
ytick = \empty,
axis equal image,
axis on top,
clip = false
]

\addplot[ultra thick, no marks] coordinates {(1.5,1) (3.5,1) (3.5,3) (1.5,3) (1.5,1)};
\addplot[ultra thick, no marks, dashed] coordinates {(0,1) (1.5,1) (1.5,0)};
\addplot[ultra thick, no marks, dashed] coordinates {(0,3) (2,3)};
\addplot[ultra thick, no marks, dashed] coordinates {(3.5,1) (3.5,0)};

\addplot[no marks] coordinates {(1,0)} node[below] {$u$};
\addplot[no marks] coordinates {(3.5,0)} node[below] {$u+h$};
\addplot[no marks] coordinates {(0,1)} node[left] {$v$};
\addplot[no marks] coordinates {(0,3)} node[left] {$v+k$};

\addplot[no marks] coordinates {(1.5,1)} node[above left] {$A_0$};
\addplot[no marks] coordinates {(1.5,3)} node[above left] {$D_0$};
\addplot[no marks] coordinates {(3.5,3)} node[above right] {$C_0$};
\addplot[no marks] coordinates {(3.5,1)} node[above right] {$B_0$};
\end{axis}
\end{tikzpicture}

terza figura

codice terza figura

\begin{tikzpicture}
\begin{axis}[
scale=0.8,
axis x line=center,
axis y line=center,
xmin = 0,
xmax = 5,
ymin = 0,
ymax = 5,
xtick = \empty,
ytick = \empty,
axis equal image,
axis on top,
clip = false
]

\addplot[-stealth,ultra thick] coordinates {(1,1.5) (2,3.5)};
\addplot[-stealth,ultra thick] coordinates {(1,1.5) (3.5,2)};
\addplot[ultra thick,dashed] coordinates {(2,3.5) (4.5,4)};
\addplot[ultra thick,dashed] coordinates {(3.5,2) (4.5,4)};
\addplot[ultra thick,dashed] coordinates {(0,1.5) (1,1.5) (1,0)};

\addplot[no marks] coordinates {(1,0)} node[below] {$x$};
\addplot[no marks] coordinates {(0,1.5)} node[left] {$y$};
\addplot[no marks] coordinates {(1,1.5)} node[below right] {$A_1$};
\addplot[no marks] coordinates {(1.5,2.5)} node[left] {$V_1$};
\addplot[no marks] coordinates {(2.5,1.75)} node[below] {$V_2$};
\end{axis}
\end{tikzpicture}

quarta figura

codice quarta figura

\begin{tikzpicture}
\begin{axis}[
scale=0.8,
axis x line=center,
axis y line=center,
xmin = -4,
xmax = 4,
ymin = -4,
ymax = 4,
xlabel = {$u$},
ylabel = {$v$},
extra x ticks = {0},
extra x tick label = {$\hspace{0.5cm}O$},
xtick = \empty,
ytick = \empty,
axis equal image,
axis on top,
clip = false,
disabledatascaling
]

\addplot[ultra thick, smooth cycle, fill=blue!50] plot coordinates {(0,1) (2,1.5) (1.5, -2) (-1, -2) (-2.5, -1) (-2.5, 1.5)} node[above right] {$\Psi^{-1}(\Omega)$};
\addplot[ultra thick, smooth cycle] plot coordinates {(2.5,2.5) (3,-3.2) (-3.2,-2) (-3.1,3)} node[above left] {$D$};
\draw[-stealth,ultra thick] (axis cs:4,3) to[bend right=-35] (axis cs:8,3);
\addplot[draw=none] coordinates {(6,4.2)} node {$\Psi$};
\draw[stealth-,ultra thick] (axis cs:4,-3) to[bend right=35] (axis cs:8,-3);
\addplot[draw=none] coordinates {(6,-4.3)} node {$\Psi^{-1}$};
\end{axis}
\end{tikzpicture}

quinta figura

codice quinta figura

\begin{tikzpicture}
\begin{axis}[
scale=0.8,
axis x line=center,
axis y line=center,
xmin = -4,
xmax = 4,
ymin = -4,
ymax = 4,
xlabel = {$x$},
ylabel = {$y$},
extra x ticks = {0},
extra x tick label = {$\hspace{0.5cm}O$},
xtick = \empty,
ytick = \empty,
axis equal image,
axis on top
]

\addplot[ultra thick, smooth cycle, fill=blue!50] plot coordinates {(0,1.5) (1, 1) (1, -0.5) (0,-1.5) (-2, -2) (-2,0) (-1,1)} node[above left] {$\Omega$};
\addplot[ultra thick, smooth] plot coordinates {(-3,5) (0,3) (2,3) (2.5,0) (2,-2) (-2,-3) (-5,1)};
\addplot[draw=none] coordinates {(1,-3)} node[right] {$E = \Psi(D)$};
\end{axis}
\end{tikzpicture}

 
 

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