X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/kahina_paper1.git/blobdiff_plain/1c032eb8576d3d2ae1b6f4a297c7437af7c26c02..d2eaa5b6b9f4ba47dbfa2aeaae51427945accf72:/paper.tex?ds=inline diff --git a/paper.tex b/paper.tex index 9e84151..04e1316 100644 --- a/paper.tex +++ b/paper.tex @@ -147,9 +147,12 @@ approximation of all the roots, starting with the Durand-Kerner (DK) method: %%\begin{center} \begin{equation} - Z_{i}=Z_{i}-\frac{P(Z_{i})}{\prod_{i\neq j}(z_{i}-z_{j})} + Z_i^{k+1}=Z_{i}^k-\frac{P(Z_i^k)}{\prod_{i\neq j}(Z_i^k-Z_j^k)} \end{equation} %%\end{center} +where $Z_i^k$ is the $i^{th}$ root of the polynomial $P$ at the +iteration $k$. + This formula is mentioned for the first time by Weiestrass~\cite{Weierstrass03} as part of the fundamental theorem @@ -161,9 +164,11 @@ in the following form by Ehrlich~\cite{Ehrlich67} and Aberth~\cite{Aberth73} uses a different iteration formula given as fellows : %%\begin{center} \begin{equation} - Z_{i}=Z_{i}-\frac{1}{{\frac {P'(Z_{i})} {P(Z_{i})}}-{\sum_{i\neq j}(z_{i}-z_{j})}}. + Z_i^{k+1}=Z_i^k-\frac{1}{{\frac {P'(Z_i^k)} {P(Z_i^k)}}-{\sum_{i\neq j}(Z_i^k-Z_j^k)}}. \end{equation} %%\end{center} +where $P'(Z)$ is the polynomial derivative of $P$ evaluated in the +point $Z$. Aberth, Ehrlich and Farmer-Loizou~\cite{Loizon83} have proved that the Ehrlich-Aberth method (EA) has a cubic order of convergence for simple roots whereas the Durand-Kerner has a quadratic order of convergence. @@ -712,9 +717,20 @@ This figure show the execution time of the both algorithm EA and DK with sparse \label{fig:01} \end{figure} -\bibliography{mybibfile} +\subsubsection{The execution time of Ehrlich-Aberth algorithm on OpenMP(1 core, 4 cores) vs. on a Tesla GPU} + +\begin{figure}[H] +\centering + \includegraphics[width=0.8\textwidth]{figures/openMP-GPU} +\caption{The execution time of Ehrlich-Aberth algorithm on OpenMP(1core, 4cores) and GPU(Tesla k40)} +\label{fig:01} +\end{figure} + + \section{Conclusion and perspective} +\bibliography{mybibfile} + \end{document}