From 6c60fbc7652eb8a01fdb8e8b0b2c59ced16e397e Mon Sep 17 00:00:00 2001
From: Jan Grewe <jan.grewe@g-node.org>
Date: Mon, 29 Oct 2018 21:48:14 +0100
Subject: [PATCH] [exercise5] control flow, some rewording
---
programming/exercises/control_flow.tex | 47 ++++++++++++++------------
1 file changed, 26 insertions(+), 21 deletions(-)
diff --git a/programming/exercises/control_flow.tex b/programming/exercises/control_flow.tex
index 725a81e..84d48da 100644
--- a/programming/exercises/control_flow.tex
+++ b/programming/exercises/control_flow.tex
@@ -14,7 +14,7 @@
%%%%% text size %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\usepackage[left=20mm,right=20mm,top=25mm,bottom=25mm]{geometry}
\pagestyle{headandfoot}
-\header{{\bfseries\large Exercise 4}}{{\bfseries\large Control Flow}}{{\bfseries\large 30. October, 2017}}
+\header{{\bfseries\large Exercise 5}}{{\bfseries\large Control Flow}}{{\bfseries\large 30. October, 2018}}
\firstpagefooter{Dr. Jan Grewe}{Phone: 29 74588}{Email:
jan.grewe@uni-tuebingen.de}
\runningfooter{}{\thepage}{}
@@ -33,39 +33,44 @@
\begin{center}
\textbf{\Large Introduction to scientific computing}\\[1ex]
{\large Jan Grewe, Jan Benda}\\[-3ex]
- Abteilung Neuroethologie \hfill --- \hfill Institut f\"ur Neurobiologie \hfill --- \hfill \includegraphics[width=0.28\textwidth]{UT_WBMW_Black_RGB} \\
+ Neuroethologie \hfill --- \hfill Institute for Neurobiology \hfill --- \hfill \includegraphics[width=0.28\textwidth]{UT_WBMW_Black_RGB} \\
\end{center}
-The exercises are meant for self-monitoring, revision of the lecture
-topic. You should try to solve them on your own. Your solution should
-be submitted as a single script (m-file) in the Ilias system. Each
-task should be solved in its own ``cell''. Each cell must be
-executable on its own. The file should be named according to the following pattern:
-``variables\_datatypes\_\{lastname\}.m'' benannt werden
+The exercises are meant for self-monitoring and revision of the
+lecture. You should try to solve them on your own. Your solution
+should be submitted as a single script (m-file) in the Ilias
+system. Each task should be solved in its own ``cell''. Each cell must
+be executable on its own. The file should be named according to the
+following pattern: ``variables\_datatypes\_\{lastname\}.m''
(e.g. variables\_datentypes\_mueller.m).
\begin{questions}
\question Implement \code{for} loops in which the \emph{running variable}:
\begin{parts}
\part ... assumes values from 0 to 10. Print the value of the running variable for each iteration step.
+ \begin{solution}
+ for i = 1:10
+ disp(i);
+ end;
+ \end{solution}
\part ... assumes values from 10 to 0. Print out the value for each iteration.
\part ... assumes values from 0 to 1 in steps of 0.1. Print out the value for each iteration.
\end{parts}
- \question Indexing in vectros:
+ \question Indexing in vectors:
\begin{parts}
- \part Define a vector \code{x} that contains values from 1:100.
+ \part Define a vector \code{x} that contains values ranging from 101 to 200.
\part Use a \code{for} loop to print each element of \code{x}. Use the running variable for the indexing.
\begin{solution}
\code{for i = 1:length(x); disp(x(i)); end}
\end{solution}
- \part Do the same without using the running variable for indexing.
+ \part Do the same without use the running variable directly (not for indexing).
\begin{solution}
\code{for i : x; disp(i); end;}
\end{solution}
\end{parts}
- \question Create a vector \verb+x+ that contains 50 random numbers in the range 0 - 10.
+ \question Create a vector \verb+x+ that contains 50 random numbers in the value range 0 - 10.
\begin{parts}
\part Use a loop to calculate the arithmetic mean. The mean is defined as:
$\overline{x}=\frac{1}{n}\sum\limits_{i=0}^{n}x_i $.
@@ -74,20 +79,20 @@ executable on its own. The file should be named according to the following patte
\part Search the MATLAB help for functions that do the calculations for you :-).
\end{parts}
- \question Implement a\code{while} loop
+ \question Implement a \code{while} loop
\begin{parts}
- \part ... that iterates 100 times. Print out the current iteration number.
+ \part ... that iterates 100 times. Print out the current iteration number.
\part ... iterates endlessly. You can interrupt the execution with the command \code{Strg + C}.
\end{parts}
- \question Use an endless \code{while} loop to individually print out the elements of a vector that contains 10 elements.
+ \question Use an endless \code{while} loop to individually print out the elements of a vector that contains 10 elements. Stop the execution after all elements have been printed.
\question Use the endless \verb+while+ loop to draw random numbers
- (\verb+randn+) until you it is larger than 1.33.
+ (\verb+randn+) until you hit one that is larger than 1.33.
\begin{parts}
\part Count the number of required iterations.
- \part Use a \code{for} loop to run the previous test 1000 times. Remeber all counts and calculate the mean of it.
- \part Create a plot that schows for each of the 1000 trials, how often you had to draw.
+ \part Use a \code{for} loop to run the previous test 1000 times. Remember all counts and calculate the mean of it.
+ \part Create a plot that shows for each of the 1000 trials, how often you had to draw.
\part Play around with the threshold. What happens?
\end{parts}
@@ -100,19 +105,19 @@ executable on its own. The file should be named according to the following patte
\end{parts}
\question Test the random number generator! To do so count the
- number of elements that fall in the classes defined by the edges
+ number of elements that fall into the classes defined by the edges
[0.0, 0.2, 0.4, 0.6, 0.8, 1.0]. Store the results in a vector. Use a
loop to draw 1000 random numbers with \verb+rand()+ (see help). What
would be the expectation? What is the result?
- \question String parsing: It is quite common to use the names of datasets to encode the conditions under which they were recorded. To find out the required information we have to \emph{parse} he name.
+ \question String parsing: It is quite common to use the names of datasets to encode the conditions under which they were recorded. To find out the required information we have to \emph{parse} the name.
\begin{parts}
\part Create a variable
\verb+filename = '2015-10-12_100Hz_1.25V.dat'+. Obviously, the
underscore was used as a delimiter.
\part Use a \verb+for+ loop to find the positions of the underscores and store these in a vector.
\part Use a second loop to iterate over the previously filled `position' vector and use this information to
- cut filename appropriately.
+ cut \verb+filename+ appropriately.
\part Print out the individual parts.
\end{parts}