X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/rairo15.git/blobdiff_plain/586298b57c6e1cec5566bbe692ac21c4c701fd51..f18e5003b9da99d6565d366a1a9d56f8d893e5d9:/preliminaries.tex?ds=sidebyside diff --git a/preliminaries.tex b/preliminaries.tex index 6d837a1..8f7774a 100644 --- a/preliminaries.tex +++ b/preliminaries.tex @@ -1,14 +1,11 @@ - - - In what follows, we consider the Boolean algebra on the set $\Bool=\{0,1\}$ with the classical operators of conjunction '.', of disjunction '+', of negation '$\overline{~}$', and of disjunctive union $\oplus$. Let $n$ be a positive integer. A {\emph{Boolean map} $f$ is -a function from the Boolean domain - to itself +a function from $\Bool^n$ +to itself such that $x=(x_1,\dots,x_n)$ maps to $f(x)=(f_1(x),\dots,f_n(x))$. Functions are iterated as follows. @@ -37,52 +34,46 @@ the graph $\Gamma(f)$ contains an arc from $x$ to $F_f(i,x)$. Let us consider for instance $n=3$. Let $f^*: \Bool^3 \rightarrow \Bool^3$ be defined by - $f^*(x_1,x_2,x_3) = (x_2 \oplus x_3, \overline{x_1}\overline{x_3} + x_1\overline{x_2}, -\overline{x_1}\overline{x_3} + x_1x_2)$ +\overline{x_1}\overline{x_3} + x_1x_2)$. The iteration graph $\Gamma(f^*)$ of this function is given in Figure~\ref{fig:iteration:f*}. \vspace{-1em} \begin{figure}[ht] \begin{center} -\includegraphics[scale=0.5]{images/iter_f0b} +\includegraphics[scale=0.5]{images/iter_f0c} \end{center} \vspace{-0.5em} \caption{Iteration Graph $\Gamma(f^*)$ of the function $f^*$}\label{fig:iteration:f*} \end{figure} \end{xpl} -\vspace{-0.5em} -It is easy to associate a Markov Matrix $M$ to such a graph $G(f)$ -as follows: - -$M_{ij} = \frac{1}{n}$ if there is an edge from $i$ to $j$ in $\Gamma(f)$ and $i \neq j$; $M_{ii} = 1 - \sum\limits_{j=1, j\neq i}^n M_{ij}$; and $M_{ij} = 0$ otherwise. - -\begin{xpl} -The Markov matrix associated to the function $f^*$ is - -\[ -M=\dfrac{1}{3} \left( -\begin{array}{llllllll} -1&1&1&0&0&0&0&0 \\ -1&1&0&0&0&1&0&0 \\ -0&0&1&1&0&0&1&0 \\ -0&1&1&1&0&0&0&0 \\ -1&0&0&0&1&0&1&0 \\ -0&0&0&0&1&1&0&1 \\ -0&0&0&0&1&0&1&1 \\ -0&0&0&1&0&1&0&1 -\end{array} -\right) -\] - - - - - -\end{xpl} +% \vspace{-0.5em} +% It is easy to associate a Markov Matrix $M$ to such a graph $G(f)$ +% as follows: + +% $M_{ij} = \frac{1}{n}$ if there is an edge from $i$ to $j$ in $\Gamma(f)$ and $i \neq j$; $M_{ii} = 1 - \sum\limits_{j=1, j\neq i}^n M_{ij}$; and $M_{ij} = 0$ otherwise. + +% \begin{xpl} +% The Markov matrix associated to the function $f^*$ is + +% \[ +% M=\dfrac{1}{3} \left( +% \begin{array}{llllllll} +% 1&1&1&0&0&0&0&0 \\ +% 1&1&0&0&0&1&0&0 \\ +% 0&0&1&1&0&0&1&0 \\ +% 0&1&1&1&0&0&0&0 \\ +% 1&0&0&0&1&0&1&0 \\ +% 0&0&0&0&1&1&0&1 \\ +% 0&0&0&0&1&0&1&1 \\ +% 0&0&0&1&0&1&0&1 +% \end{array} +% \right) +% \] +%\end{xpl} It is usual to check whether rows of such kind of matrices