Tikz – esempio 21

Benvenuti nel nostro esempio 21 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 20 e il successivo Tikz – esempio 22 per ulteriore materiale.

Buona lettura!

 

Prima figura

 

 

codice prima figura

 

\begin{tikzpicture}
\begin{axis}[
width = 0.7\textwidth,
height = 0.7\textwidth,
xtick = \empty,
ytick = \empty,
axis on top,
axis equal image,
axis x line=center,
axis y line=center,
xmin = -3.5,
xmax = 3.5,
ymin = -3.5,
ymax = 3.5,
xlabel = {$x$},
ylabel = {$y$},
ylabel style={anchor=north east},
extra x ticks = {0},
extra x tick label = {$\hspace{0.4cm}O$},
disabledatascaling,
]
\draw[thick,red,fill=YellowOrange] (axis cs:0,0) ellipse [x radius=2, y radius=1,rotate=180];
\addplot[mark=*] coordinates {(2,0)} node[below right] {$(2,0)$};
\addplot[mark=*] coordinates {(-2,0)} node[below left] {$(-2,0)$};
\addplot[mark=*] coordinates {(0,1)} node[above right] {$(0,1)$};
\addplot[mark=*] coordinates {(0,-1)} node[below right] {$(-1,0)$};
\end{axis}
\end{tikzpicture}

 

seconda figura

 

 

codice seconda figura

 

\begin{tikzpicture}
\begin{axis}[
width = 0.7\textwidth,
height = 0.7\textwidth,
xtick = \empty,
ytick = \empty,
axis on top,
axis equal image,
axis x line=center,
axis y line=center,
xmin = -3.5,
xmax = 4.5,
ymin = -3.5,
ymax = 3.5,
xlabel = {$x$},
ylabel = {$y$},
ylabel style={anchor=north east},
extra x ticks = {0},
extra x tick label = {$\hspace{0.4cm}O$},
disabledatascaling,
]
\addplot[mark=*,red] coordinates {(0,0) (-1,{sqrt(3)/2})};
\addplot[mark=*,red] coordinates {(0,0) (-1,- {sqrt(3)/2})};
\addplot[mark=*,red] coordinates {(0,0) (-2,0)};
\addplot[mark=*,red] coordinates {(0,0) (2,0)};
\draw[thick,red] (axis cs:0,0) ellipse [x radius=2, y radius=1,rotate=180];
\draw (axis cs:-1,1.4) node[red] {$t=\frac{2}{3}\pi$};
\draw (axis cs:-1,-1.4) node[red] {$t=\frac{4}{3}\pi$};
\draw (axis cs:-2.6,0.4) node[red] {$t=\pi$};
\draw (axis cs:2.8,0.4) node[red] {$t=0,\,2\pi$};
\end{axis}
\end{tikzpicture}

 

terza figura

 

 

codice terza figura

 

\begin{tikzpicture}
\begin{axis}[
width = 0.7\textwidth,
height = 0.7\textwidth,
xtick = \empty,
ytick = \empty,
axis on top,
axis equal image,
axis x line=center,
axis y line=center,
xmin = -3.5,
xmax = 4.5,
ymin = -3.5,
ymax = 3.5,
xlabel = {$x$},
ylabel = {$y$},
ylabel style={anchor=north east},
extra x ticks = {0},
extra x tick label = {$\hspace{0.4cm}O$},
disabledatascaling,
]
\addplot[mark=*,red] coordinates {(0,0) (-1,{sqrt(3)/2})};
\addplot[mark=*,blue] coordinates {(0,0) (-0.25,0)};
\addplot[mark=*,red] coordinates {(0,0) (-1,- {sqrt(3)/2})};
\addplot[mark=*,red] coordinates {(0,0) (-2,0)};
\addplot[mark=*,red] coordinates {(0,0) (2,0)};
\draw[thick,red,fill=YellowOrange] (axis cs:0,0) ellipse [x radius=2, y radius=1,rotate=180];
\draw (axis cs:-0.25,-0.25) node[blue] {$P_1$};
\draw (axis cs:-1,1.4) node[red] {$P_4$};
\draw (axis cs:-1,-1.4) node[red] {$P_5$};
\draw (axis cs:-2.6,0.4) node[red] {$P_3$};
\draw (axis cs:2.8,0.4) node[red] {$P_2$};
\end{axis}
\end{tikzpicture}

 

quarta figura

 

codice quarta figura

 

\begin{tikzpicture}
\begin{axis}[
width = 0.7\textwidth,
height = 0.7\textwidth,
axis on top ,
xtick = \empty,
ytick = \empty,
axis equal image,
axis x line=center,
axis y line=center,
xmin = -6,
xmax = 6,
ymin = -4,
ymax = 7,
xlabel = {$x$},
ylabel = {$y$},
extra x ticks = {0},
extra x tick label = {$\hspace{0.4cm}0$},
y label style={anchor=north east}
]
\addplot[mark=*,very thick,red] coordinates { (-1,-1) (-1,4) (1.5,-1)(-1,-1)};
\addplot[mark=*] coordinates {(-1,-1)} node[below left] {$B=(-1,-1)$};
\addplot[mark=*] coordinates {(-1,4)} node[below left] {$A=(-1,4)$};
\addplot[mark=*] coordinates {(1.5,-1)} node[below right] {$\,\,C=\left(\dfrac{3}{2},-1\right)$};
\addplot[very thick,dashed,samples=100,domain=3:-3,red,,name path=retta 1] {-2*x+2};
\addplot[very thick,samples=100,domain=3:-3,red,dashed,,name path=retta 2] {-1};
\addplot[very thick,red,dashed] coordinates { (-1,4) (-1,6)};
\addplot[very thick,red,dashed] coordinates { (-1,-1) (-1,-5)};
\addplot[TealBlue!30] fill between[of=retta 1 and retta 2, soft clip={domain=-1:1.5}];
\draw (axis cs:-2,-2.5) node[red] {$x=-1$};
\draw (axis cs:1.5,-3.5) node[red] {$y=-2x+2$};
\draw (axis cs:2.4,-0.7) node[red] {$y=-1$};
\draw (axis cs:1.4,1.4) node[rotate=0] [red]{$\partial E$};
\draw (axis cs:-0.3,0.4) node[rotate=0] [BlueViolet]{$E^\circ$};
\end{axis}
\end{tikzpicture}

 

quinta figura

 

 

codice quinta figura

 

\begin{tikzpicture}
\begin{axis}[
width = 0.7\textwidth,
height = 0.7\textwidth,
xtick = \empty,
ytick = \empty,
axis on top,
axis equal image,
axis x line=center,
axis y line=center,
xmin = -4,
xmax = 4,
ymin = -4,
ymax = 4,
xlabel = {$x$},
ylabel = {$y$},
extra x tick label = {$\hspace{0.4cm}O$},
disabledatascaling,
]
\draw[thick,red,fill=Lavender] (axis cs:0,0) circle [radius=2];
\addplot[mark=*] coordinates {(2,0)} node[below right] {$(2,0)$};
\addplot[mark=*] coordinates {(-2,0)} node[below left] {$(-2,0)$};
\addplot[mark=*] coordinates {(0,2)} node[above right] {$(0,2)$};
\addplot[mark=*] coordinates {(0,-2)} node[below right] {$(0,-2)$};
\draw (axis cs:0.3,0.25) node[rotate=0] {$A^\circ$};
\draw (axis cs:2.3,1.4) node[rotate=0] [red]{$\partial A$};
\end{axis}
\end{tikzpicture}

 
 

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