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\begin{document}

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\section*{Software engineering in climate science}

\hypertarget{contents}{}\section*{{Contents}}\label{contents}

\noindent\hyperlink{idea}{Idea}\dotfill \pageref*{idea} \linebreak
\noindent\hyperlink{details}{Details}\dotfill \pageref*{details} \linebreak
\noindent\hyperlink{quality_management}{Quality Management}\dotfill \pageref*{quality_management} \linebreak
\noindent\hyperlink{verification_and_validation}{Verification and Validation}\dotfill \pageref*{verification_and_validation} \linebreak
\noindent\hyperlink{references}{References}\dotfill \pageref*{references} \linebreak


\hypertarget{idea}{}\subsection*{{Idea}}\label{idea}

\textbf{Software engineering} is the branch of study that is concerned with the overall quality, structure and maintainability of big software systems. When programming is compared to masonry, then software engineering can be compared to architecture.

\hypertarget{details}{}\subsection*{{Details}}\label{details}

\hypertarget{quality_management}{}\subsubsection*{{Quality Management}}\label{quality_management}

\hypertarget{verification_and_validation}{}\subsubsection*{{Verification and Validation}}\label{verification_and_validation}

There is an important difference in the meaning of verification and validation in the context of quality management of software systems:

\begin{itemize}%
\item \textbf{verification} is about the question if the system \textbf{does things right},


\item \textbf{validation} is about the question if the system \textbf{does the right thing}.



\end{itemize}
\emph{Example}: Let's say we would like to have a function that computes the price of a book, and we write a specification for that function saying ``calculate the price of a book in dollars by multiplying the ISBN with 0.5''.

We employ a programmer who programs the function. We test the function by passing the number ``20'' into the function, it returns ``10 dollars''. Now

\begin{itemize}%
\item \emph{verification} says that the function is okay, because it does exactly what it should do, while


\item \emph{validation} says that the function and the specification are faulty, because there is no connection of the ISBN of a book and its price whatsoever.



\end{itemize}
\hypertarget{references}{}\subsection*{{References}}\label{references}

An interesting blog is

\begin{itemize}%
\item Steve Easterbrook: \href{http://www.easterbrook.ca/steve/}{Serendipity}

\end{itemize}
A history of the development and assessment of the current status of the climate science infrastructure can be found here:

\begin{itemize}%
\item Paul N. Edwards: \emph{A Vast Machine: Computer Models, Climate Data, and the Politics of Global Warming}

\end{itemize}
category: software, climate [[!redirects software engineering]] [[!redirects software engineering in climate science]] [[!redirects IV\&V]]



\end{document}