Merge branch 'AndreasFMueller:master' into master

1 files changed, 32 insertions, 0 deletions

diff --git a/buch/papers/ellfilter/tikz/filter.tikz.tex b/buch/papers/ellfilter/tikz/filter.tikz.tex
new file mode 100644
index 0000000..769602a
--- /dev/null
+++ b/buch/papers/ellfilter/tikz/filter.tikz.tex
@@ -0,0 +1,32 @@
+\begin{tikzpicture}[>=stealth', auto, node distance=2cm, scale=1.2]
+
+    \tikzstyle{zero} = [draw, circle, inner sep =0, minimum height=0.15cm]
+
+    \tikzset{pole/.style={cross out, draw=black, minimum size=(0.15cm-\pgflinewidth), inner sep=0pt, outer sep=0pt}}
+
+    \begin{scope}[xscale=3, yscale=2.5]
+
+        \fill[darkgreen!15] (0,0) rectangle  (1,1);
+        \node[darkgreen] at (0.5,0.5) {Durchlassbereich};
+        \fill[orange!15] (1,0) rectangle  (2.5,1);
+        \node[orange] at (1.75,0.5) {Sperrbereich};
+
+        \draw[gray, ->] (0,0) -- (0,1.25) node[anchor=south]{$|H(\Omega)|$};
+        \draw[gray, ->] (0,0) -- (2.75,0) node[anchor=west]{$\Omega$};
+
+        \draw[dashed] (0,0.707) node[left] {$\sqrt{\frac{1}{1+\varepsilon^2}}$} -| (1,0) node[below] {$\Omega_p$};
+        \draw[dashed] (0,0.707) node[left] {$\sqrt{\frac{1}{1+\varepsilon^2}}$} -| (1,0) node[below] {$\Omega_p$};
+
+        \node[left] at(0,1) {$1$};
+
+        \draw[red, thick] (0,1) -- (1,1) -- (1,0) -- (2.5,0);
+
+        \node[anchor=north, red] at (0.5,1) {Ideal};
+
+        \draw[thick, domain=0:2.5,  variable=\x, smooth, samples=200] plot
+        ({\x}, {sqrt(abs(1/ (1 + \x^10)))});
+        \node[anchor=south] at (0.5,1) {Butterworth ($N=5$)};
+
+    \end{scope}
+
+\end{tikzpicture}