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diff --git a/Master/texmf-dist/source/latex/mh/breqn-technotes.tex b/Master/texmf-dist/source/latex/mh/breqn-technotes.tex deleted file mode 100644 index e8c6174cbbf..00000000000 --- a/Master/texmf-dist/source/latex/mh/breqn-technotes.tex +++ /dev/null @@ -1,145 +0,0 @@ -\documentclass{article} -\usepackage{lmodern} -\usepackage[T1]{fontenc} -\usepackage{breqn} -\def\eqnumside{L} -\providecommand*\cs[1]{\texttt{\textbackslash#1}} - -\usepackage{hyperref} - -\title{Technical notes on equation breaking} -\author{Michael J.\ Downes \and Morten H\o gholm} -\begin{document} - -\maketitle - - -\section{Tag placement} - -The method used by the breqn package to place the equation number is -rather more complicated than you might think, and the whole reason is -to allow the number to stay properly centered on the total height even -when the height fluctuates due to stretching or shrinking of the page. - - -Consider the following equation: -\begin{dmath}[number={3.15}] - N_{0} \simeq \left( \frac{\nu}{\lVert u\rVert_{H^{i}}} \right) - \lvert I\rvert^{-1/2} -\end{dmath} -It will have only one line, if the column width is not too narrow. - -Scrutinizing the vertical list will shed light on some of the basic properties -shared by all breqn equations. After that we will look at what would happen if -two or more lines were needed. The numbers added on the left in the following -\cs{showlists} output mark the points of interest. -\begin{verbatim} -[1] \penalty 10000 - \glue(\abovedisplayskip) 0.0 - \penalty 10000 - \glue(\belowdisplayskip) 0.0 -[2] \glue 4.0 plus 4.0 - \glue(\lineskip) 1.0 -[3] \vbox(16.53902+0.0)x0.0, glue set 16.53902fil - .\glue 0.0 plus 1.0fil minus 1.0fil - \penalty 10000 -[4] \glue -8.51945 -[5] \hbox(7.5+2.5)x25.55563 - .\OT1/cmr/m/n/10 ( - .\OT1/cmr/m/n/10 3 - .\OT1/cmr/m/n/10 . - .\OT1/cmr/m/n/10 1 - .\OT1/cmr/m/n/10 5 - .\kern 0.0 - .\OT1/cmr/m/n/10 ) - \penalty 10000 -[6] \glue(\parskip) -18.01956 -[7] \hbox(16.53902+9.50012)x360.0, glue set 1.78647 -\end{verbatim} -\begin{enumerate} -\item These four lines are a hidden display structure from \TeX's - primitive \texttt{\$\$} mechanism. It is used only to get the value - of \cs{predisplaysize} so that we can later calculate by hand - whether to use the short display skips or the regular ones. (The - reason that we have to do it by hand traces back to the fact that - \TeX\ 3.x does not allow unhboxing in math mode.) The penalties come - from \cs{predisplaypenalty} and \cs{postdisplaypenalty}, which were - locally set to 10000 to ensure there would be no unintended page - breaks at these glue nodes. - -\item These two glue nodes are the ones that would normally have been - produced at the top of a display; the first one is the above-display - skip node (though we had to put it in by hand with \cs{vskip}) and - the second one is the usual baselineskip/lineskip node. - -\item This is a dummy copy of the equation's first line, which is - thrown in here to get the proper value of baselineskip (or lineskip - in this case). Why do we need this? Because this ensures that we get - the top spacing right before we fiddle with the glue nodes - surrounding the equation number. And if the equation has a frame, - this box is a good place to add it from. - -\item This is a special glue node that brings us to the right vertical - position for adding the equation number. Its value is calculated - from the variables that you would expect, given the presence of the - dummy first line above the num- ber: starting position of the - equation, height of first line, total height of equation body. If - the equation body had more than one line, with stretchable glue - between the lines, half of the stretch would be added in this glue - node. - -\item The hbox containing the equation number. - -\item Backspace to bring the equation body to the right starting point. We use - \cs{parskip} to put this glue in place because we're going to get a - parskip node here in any case when we add the equation body with (in - essence). If we didn't do this we'd get two glue nodes instead of - one, to no purpose. - -\cs{\noindent} \cs{unhbox}\cs{EQ@box}. - - -\item And lastly we see here the first line of the equation body, - which appears to have height 16.5pt and depth 9.5pt. -\end{enumerate} - -For comparison, the vertical list produced from the above equation in -standard \LaTeX\ would look like this, if the same values of -columnwidth and abovedisplayskip are used: -\begin{verbatim} -[1] \penalty 10000 -[2] \glue(\abovedisplayskip) 4.0 plus 4.0 - \glue(\lineskip) 1.0 - \hbox(16.53902+9.50012)x232.94844 -[3] .\hbox(7.5+2.5)x25.55563 - ..\hbox(7.5+2.5)x25.55563 - ...\OT1/cmr/m/n/10 ( - ...\OT1/cmr/m/n/10 3 - ...\OT1/cmr/m/n/10 . - ...\OT1/cmr/m/n/10 1 - ...\OT1/cmr/m/n/10 5 - ...\kern 0.0 - ...\OT1/cmr/m/n/10 ) - .\kern101.49591 -[4] .\hbox(16.53902+9.50012)x105.8969 - ... -[5] \penalty 0 -[6] \glue(\belowdisplayskip) 4.0 plus 4.0 - \glue(\lineskip) 1.0 - \hbox(6.94444+1.94444)x345.0, glue set 62.1106fil -\end{verbatim} - -\begin{enumerate} - \item \cs{predisplaypenalty} - \item \cs{abovedisplayskip} - \item equation number box - \item equation body - \item \cs{postdisplaypenaltly} - \item \cs{belowdisplayskip} -\end{enumerate} - - - - - -\end{document}
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