From 04c94902782997662564f77b59a63924659569af Mon Sep 17 00:00:00 2001 From: Robin Clark Date: Sun, 29 Aug 2010 13:26:08 +0100 Subject: [PATCH] . --- eulerg/eulerg.tex | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) diff --git a/eulerg/eulerg.tex b/eulerg/eulerg.tex index 8171af6..7c1216f 100644 --- a/eulerg/eulerg.tex +++ b/eulerg/eulerg.tex @@ -71,7 +71,7 @@ processing and parsing of the diagram without resorting to extra area operations The set theory term `intersection' can apply to both the curves overlapping and to the sub-set case. Intersection in a concrete diagram can mean two curves bisecting. -For instance in diagram \ref{fig:eulerg1} the set theoretic intersection between +For instance in figure \ref{fig:eulerg1} the set theoretic intersection between $A$ and $B$ exists, even though the curves do not bisect in the concrete plane. $$ A \cap B \neq \emptyset $$ @@ -163,7 +163,11 @@ $$ A {\enc} C $$ As the relationships {\em enclosure} and {\pic} are mutually exclusive and {\em enclosure} is transitive and {\pic} is not, we can represent an {\em enclosure} relationship as a directed vertice and -{\pic} as non-directed. +{\pic} as non-directed on the same graph. +Figures \ref{fig:eulerg1} and \ref{fig:eulergenc} show euler diagrams with corresponding +graphs. The next section will introduce the concept of a {\pic} +and will describe graphs where both enclosure and pair-wise +intersection are represented on the same graph. \pagebreak[1] \section{The {\pic}} @@ -257,7 +261,7 @@ Because enclosure is a directed relationship and {\em pair-wise intersection} is we can represent them both on the same graph, see figure \ref{fig:eulerg_pic_g_a}. \begin{figure}[h] \centering - \includegraphics[width=200pt,bb=0 0 330 162,keepaspectratio=true]{./eulerg/eulerg_pic_g_a.jpg} + \includegraphics[width=300pt,bb=0 0 330 162,keepaspectratio=true]{./eulerg/eulerg_pic_g_a.jpg} % eulerg_pic_g_a.jpg: 330x162 pixel, 72dpi, 11.64x5.72 cm, bb=0 0 330 162 \caption{Graph of Euler diagram in figure \ref{fig:eulerg_pic}.} \label{fig:eulerg_pic_g_a} @@ -276,14 +280,15 @@ in order to show that contour A encloses all contours in $PIC1$. \begin{figure}[h] \centering - \includegraphics[width=200pt,bb=0 0 330 162]{./eulerg/eulerg_pic_g_a_unc.jpg} + \includegraphics[width=300pt,bb=0 0 330 162]{./eulerg/eulerg_pic_g_a_unc.jpg} % eulerg_pic_g_a_unc.jpg: 330x162 pixel, 72dpi, 11.64x5.72 cm, bb=0 0 330 162 \caption{Uncluttered graph of Euler diagram in figure \ref{fig:eulerg_pic}.} \label{fig:eulerg_pic_g_a_unc} \end{figure} -\pagebreak[1] +%\pagebreak[9] +\clearpage \section{Reduction of searches \\ for available zones} Another property of any {\pic} $P$, is that @@ -306,20 +311,24 @@ that are not, or would not become members of the {\pic} $P$. That is to say, the the number of zones within a {\pic} is not affected by changes in the diagram that do not alter the {\pic}. This allows us to analyses {\pic}s separately, thus reducing the $2^N$ overhead of analysing an Euler diagram for available zones. - +\pagebreak[3] \subsection{Available Zone Searching} The available zones in an Euler diagram represent set theoretic combinations that can be used in the diagram. %For FMMD analyis, the test~cases Searching for an available zone involves finding out if the intersection exists, and then determining whether it is covered up -by any other contours. A brute force search for available zones using area operations +by any other contours. +A brute force search for available zones using area operations is therefore of the order $N.2^N$ (where N is the number of contours in the diagram). -By using the result in definition \ref{picreduction}, we can break the diagram into small segments -(the {\pic}s) which have an order $|P|.2^{|P|}$. +Using $|P|$ to represent the number of conoutrs within a {\pic} +and $K$ to represent the number of {\pic}s in a diagram, +using the result in definition \ref{picreduction}, we can break the diagram into small segments +(the {\pic}s) which have an order $K.2^{|P|}$. +The exponential $2^N$ overhead is thus broken down into several smaller $2^{|P|}$ operations. The order of area operations is generally\footnote{In the case where the diagram is not comprised of just one {\pic}, which has no enclosing contours.} -reduced by requiring several $|P|.2^{|P|}$ -instead of $N.2^N$ as $P \leq N$. +reduced by requiring several $K.|P|.2^{|P|}$ +instead of $N.2^N$ as $K < N$. \vspace{40pt}