From 01298b95d9de1814c984d8861305850ee04b7452 Mon Sep 17 00:00:00 2001
From: Jan Grewe <jan.grewe@g-node.org>
Date: Fri, 23 Feb 2018 17:21:55 +0100
Subject: [PATCH] [plotting] add animations

---
 plotting/lecture/plotting-chapter.tex |  6 ----
 plotting/lecture/plotting.tex         | 44 +++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/plotting/lecture/plotting-chapter.tex b/plotting/lecture/plotting-chapter.tex
index 4dd0a9d..f0ac90c 100644
--- a/plotting/lecture/plotting-chapter.tex
+++ b/plotting/lecture/plotting-chapter.tex
@@ -16,8 +16,6 @@
 
 \input{plotting}
 
-\subsection{Error bars and error areas}
-
 \subsection{Scatter plot}
 
 \subsection{Histograms}
@@ -28,10 +26,6 @@
 
 \subsection{Polar plot}
 
-\subsection{print instead of saveas????}
-
-\subsection{Movies and animations}
-
 \section{TODO}
 \begin{itemize}
 \item Beispiele schlechter plots sollten mehr Bezug zu den Typen von
diff --git a/plotting/lecture/plotting.tex b/plotting/lecture/plotting.tex
index 4bc7f2d..badb26e 100644
--- a/plotting/lecture/plotting.tex
+++ b/plotting/lecture/plotting.tex
@@ -629,6 +629,50 @@ documentation.
   that should be drawn between two subplots?
 \end{important}
 
+\subsection{Animations and movies}
+A picture is worth a thousand words and sometimes creating animations
+or movies is worth many pictures. They can help understanding complex
+or time-dependent developments and may add some variety to a
+presentation. The following example shows how a movie can be created
+and saved to file. A similar mechanism is available to produce
+animations that are supposed to be shown within \matlab{} but for this
+we point to the documentation of the \code[movie()]{movie()}
+command. The underlying principle is the same, however. The code shown
+in listing\,\ref{animationlisting} creates an animation of a
+Lissajous figure. The basic steps are:
+\begin{enumerate}
+\item Create a figure and set some basic properties (lines 7 --- 10).
+\item Create a \code[VideoWriter()]{VideoWriter} object that, in this
+  example, takes the filename and the profile, the mpg-4 compression
+  profile, as arguments (line 12). For more options see the
+  documentation.
+\item We can set the desired framerate and the quality of the video
+  (lines 13, 14). Quality is a value between 0 and 100, where 100 is
+  the best quality but leads to the largest files. The framerate
+  defines how quickly the individual frames will switched. In our
+  example, we create 500 frames and the video framerate is
+  25\,Hz. That is, the movie will have a duration of
+  $500/25 = 20$\,seconds.
+\item Open the destination file (line 16). Opening means that the file
+  is created and opened for writing. This also implies that is has to
+  be closed after the whole process (line 31).
+\item For each frame of the video, we plot the appropriate data (we
+  use \code[scatter]{scatter} for this purpose, line 20) and ``grab''
+  the frame (line 28). Grabbing is similar to making a screenshot of
+  the figure. The \code{drawnow}{drawnow} command (line 27) is used to
+  stop the excution of the for loop until the drawing process is
+  finished.
+\item Write the frame to file (line 29).
+\item Finally, close the file (line 31).
+\end{enumerate}
+
+\lstinputlisting[caption={Making animations and saving them as a
+    movie.}, label=animationlisting, firstline=3, lastline=33,
+  basicstyle=\ttfamily\scriptsize]{movie_example.m}
+
+
+
+
 
 \section{Summary}
 A good plot of scientific data displays the data completely and