pep-material: comparison cws/cw01.tex

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-:01ee4b576eb2
+:018b9c12ee1f
 \mbox{}\hfill\textit{coupled with judiciously placed print statements.''}\smallskip\\
 \mbox{}\hfill\textit{ --- Brian W. Kernighan, in Unix for Beginners (1979)}\bigskip
 \noindent
-This assignemnt is about Scala and worth 10\%. The first and second
+This assignment is about Scala and worth 10\%. The first and second
 part are due on 16 November at 11pm, and the third part on 21 December
 at 11pm. You are asked to implement two programs about list
 processing and recursion. The third part is more advanced and might
 include material you have not yet seen in the first lecture.
 \bigskip
 Also note that the running time of each part will be restricted to a
 maximum of 30 seconds on my laptop.
 \DISCLAIMER{}
-\subsubsection*{Reference Implementation}
+\subsection*{Reference Implementation}
 Like the C++ assignments, the Scala assignments will work like this: you
 push your files to GitHub and receive (after sometimes a long delay) some
 automated feedback. In the end we take a snapshot of the submitted files and
 apply an automated marking script to them.
 ...
 scala> CW6a.collatz_max(6)
 ...
 \end{lstlisting}%$
+\subsection*{Hints}
+\noindent
+\textbf{For Part 1:} useful math operators: \texttt{\%} for modulo; useful
+functions: \mbox{\texttt{(1\,to\,10)}} for ranges, \texttt{.toInt},
+\texttt{.toList} for conversions, \texttt{List(...).max} for the
+maximum of a list, \texttt{List(...).indexOf(...)} for the first index of
+a value in a list.\bigskip
+\noindent
+\textbf{For Part 2 + 3:} useful string functions: \texttt{.startsWith(...)} for
+checking whether a string has a given prefix, \texttt{\_ ++ \_} for
+concatenating two strings; useful option functions: \texttt{.flatten}
+flattens a list of options such that it filters way all
+\texttt{None}'s, \texttt{Try(...).getOrElse ...} runs some code that
+might raise an exception---if yes, then a default value can be given;
+useful list functions: \texttt{.head} for obtaining the first element
+in a non-empty list, \texttt{.length} for the length of a
+list; \texttt{.filter(...)} for filtering out elements in a list; \texttt{.getLines.toList} for obtaining a list of lines from
+a file; \texttt{.split(",").toList} for splitting strings according to
+a comma.\bigskip
+\noindent
+Fortunately Scala supports operator overloading. But make sure you understand the difference between \texttt{100 / 3} and
+\texttt{100.0 / 3}!
+\newpage
 \subsection*{Part 1 (3 Marks, file collatz.scala)}
 This part is about recursion. You are asked to implement a Scala
 program that tests examples of the \emph{$3n + 1$-conjecture}, also
 called \emph{Collatz conjecture}. This conjecture can be described as
 \item 1 to 1 Million where $837,799$ takes 524 steps
 %% runs out of stack space
 %% \item[$\bullet$] $1 - 10$ million where $8,400,511$ takes 685 steps
 \end{itemize}
-\noindent
-\textbf{Hints:} useful math operators: \texttt{\%} for modulo; useful
-functions: \mbox{\texttt{(1\,to\,10)}} for ranges, \texttt{.toInt},
-\texttt{.toList} for conversions, \texttt{List(...).max} for the
-maximum of a list, \texttt{List(...).indexOf(...)} for the first index of
-a value in a list.
 \subsection*{Part 2 (3 Marks, file drumb.scala)}
 \item We do this for 40 years until January 2018 and check what would
 have become out of our \$100.
 \end{itemize}
 \noindent
-Until Yahoo was bought by Altaba this summer, historical stock market
+Until Yahoo was bought by Altaba last year, historical stock market
 data for such back-of-the-envelope calculations was freely available
-online. Unfortuantely nowadays this kind of data is difficult to
+online. Unfortunately nowadays this kind of data is more difficult to
 obtain, unless you are prepared to pay extortionate prices or be
-severely rate-limited.  Therefore this coursework comes with a number
+severely rate-limited.  Therefore this assignment comes with a number
 of files containing CSV-lists with the historical stock prices for the
 companies in our portfolios. Use these files for the following
 tasks.\bigskip
+\newpage
 \noindent
 \textbf{Tasks}
 \begin{itemize}
 \item[(1)] Write a function \texttt{get\_january\_data} that takes a
 \begin{verbatim}
 List(List(Some(311.349976), Some(20.544939)),
 List(Some(300.222351), Some(31.638695)),
 List(Some(330.555054), Some(39.478039)))
-\end{verbatim}\hfill[1 Marks]
+\end{verbatim}\hfill[1 Mark]
 \end{itemize}
 \subsection*{Advanced Part 3 (4 Marks, continue in file drumb.scala)}
 \noindent
 balance of \$100 into roughly \$101,589 for real estate and a whopping
 \$1,587,528 for blue chips.  Note when comparing these results with your
 own calculations: there might be some small rounding errors, which
 when compounded lead to moderately different values.\bigskip
-\noindent
-\textbf{Hints:} useful string functions: \texttt{.startsWith(...)} for
-checking whether a string has a given prefix, \texttt{\_ ++ \_} for
-concatenating two strings; useful option functions: \texttt{.flatten}
-flattens a list of options such that it filters way all
-\texttt{None}'s, \texttt{Try(...) getOrElse ...} runs some code that
-might raise an exception---if yes, then a default value can be given;
-useful list functions: \texttt{.head} for obtaining the first element
-in a non-empty list, \texttt{.length} for the length of a
-list.\bigskip
 \noindent
 \textbf{Moral:} Reflecting on our assumptions, we are over-estimating
 our yield in many ways: first, who can know in 1978 about what will
 turn out to be a blue chip company.  Also, since the portfolios are
 the corresponding CSV-list.  This list from the URL above should
 contain 194 lines.\medskip
 \noindent
 Write another function that can read the file \texttt{population.csv}
-from disk (the file is distributed with the coursework). This
+from disk (the file is distributed with the assignment). This
 function should take a string as argument, the file name, and again
 return a list of strings corresponding to each entry in the
 CSV-list. For \texttt{population.csv}, this list should contain 216
 lines.\hfill[1 Mark]

changeset 201	018b9c12ee1f
parent 199	54befaf23648
child 202	f7bcb27d1940