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\subsection{worstcase}
\label{labworstcase}
\noindent Name: \textbf{worstcase}\\
\phantom{aaa}searches for hard-to-round cases of a function\\[0.2cm]
\noindent Library names:\\
\verb| void sollya_lib_worstcase(sollya_obj_t, sollya_obj_t, sollya_obj_t,|\\
\verb| sollya_obj_t, sollya_obj_t, ...)|\\
\verb| void sollya_lib_v_worstcase(sollya_obj_t, sollya_obj_t, sollya_obj_t,|\\
\verb| sollya_obj_t, sollya_obj_t, va_list)|\\[0.2cm]
\noindent Usage:
\begin{center}
\textbf{worstcase}(\emph{function}, \emph{preimage precision}, \emph{preimage exponent range}, \emph{image precision}, \emph{error bound}) : (\textsf{function}, \textsf{integer}, \textsf{range}, \textsf{integer}, \textsf{constant}) $\rightarrow$ \textsf{void}\\
\textbf{worstcase}(\emph{function}, \emph{preimage precision}, \emph{preimage exponent range}, \emph{image precision}, \emph{error bound}, \emph{filename}) : (\textsf{function}, \textsf{integer}, \textsf{range}, \textsf{integer}, \textsf{constant}, \textsf{string}) $\rightarrow$ \textsf{void}\\
\end{center}
Parameters:
\begin{itemize}
\item \emph{function} represents the function to be considered
\item \emph{preimage precision} represents the precision of the preimages
\item \emph{preimage exponent range} represents the exponents in the preimage format
\item \emph{image precision} represents the precision of the format the images are to be rounded to
\item \emph{error bound} represents the upper bound for the search w.r.t. the relative rounding error
\item \emph{filename} represents a character sequence containing a filename
\end{itemize}
\noindent Description: \begin{itemize}
\item The \textbf{worstcase} command is deprecated. It searches for hard-to-round cases of
a function. The command \textbf{searchgal} has a comparable functionality.
\end{itemize}
\noindent Example 1:
\begin{center}\begin{minipage}{15cm}\begin{Verbatim}[frame=single]
> worstcase(exp(x),24,[1,2],24,1b-26);
prec = 165
x = 1.99999988079071044921875 f(x) = 7.3890552520751953125 eps = 4
.5998601423446695596184695493764120138001954979037e-9 = 2^(-27.695763)
x = 2 f(x) = 7.38905620574951171875 eps = 1.4456360874967301812222
8379395533417878125150587072e-8 = 2^(-26.043720)
\end{Verbatim}
\end{minipage}\end{center}
See also: \textbf{round} (\ref{labround}), \textbf{searchgal} (\ref{labsearchgal}), \textbf{evaluate} (\ref{labevaluate})
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