# [texhax] Left-flushed equations

Uwe Lueck uwe.lueck at web.de
Fri May 19 16:16:25 CEST 2006

Very generally: all that has been proposed so far uses TeX's basic
$$...$$. To get flush-left equations -- by which Micha certainly
doesn't mean equation numbers on the left, but he doesn't
want centered equations! with $$...$$, you would have to typeset
the formulas inside some \hbox{$\displaystyle...$\hss}.

I would rather tend to use a version of a list environment
-- so you can control the indent and the vertical spaces
as \leftmargin (\leftmargini), \topsep, and \itemsep .
Difference to usual list environments: The counter shouldn't
be reset for each environment. So introduce a new LaTeX
counter{myequation}, use \newenvironment using
\list, \endlist, and \usecounter{myequation} and such that
\end{...} stores the value of myequation and \begin{...}
uses it ... sorry, I am not at home and don't have a manual
here, and must leave this PC instantly. Some trick should
have the effect that \item does \$\displaystyle etc.

HTH -- Uwe.

Micha Hofri <hofri at WPI.EDU> schrieb am 18.05.2006 16:04:53:
>
>
> Thanks to all who responded.  What actually happens is -- nothing.
>
> I tried some of the medicine in Herbert's very welcome Math mode paper; I
> tried Barbara's straightforward redefinition, there is simply no effect.
>
> I look at the way the fleqn.clo file, which \usepackage{fleqn} loads,
> redefines the environment equation (the only one I use here) and it makes
> no direct use of these.
> In fact, the only reference to vertical motion there that I can
> see is just before displaying the equation, there is a \leavevmode
>
> Could this choice be the source of my difficulty?  Those left-flushed
> equations look just right...
>
> --Micha Hofri
>
>
> At 08:53 on 05/18/06 Barbara Beeton sent:
>
> :     Now a related question: how do I control spacing above and below displays
> :     (I need to reduce it drastically)?
> :
> :     Do I need to modify the given rubber length parameters /and/ the relevant
> :     penalties (and I am not yet sure which those be)?
> :
> : you said you're using class amsart.
> :
> : in this class there is the following definition:
> :
> :   \bigskipamount.7\baselineskip plus.7\baselineskip
> :   \medskipamount\bigskipamount \divide\medskipamount\tw@
> :   \smallskipamount\medskipamount \divide\smallskipamount\tw@
> :   \abovedisplayskip\medskipamount
> :   \belowdisplayskip \abovedisplayskip
> :   \abovedisplayshortskip\abovedisplayskip
> :   \belowdisplayshortskip\abovedisplayshortskip
> :   \jot\baselineskip \divide\jot 4 \relax
> : }
> :
> : the various "displayskip"s govern the spacing
> : above and below displays.  you want to redefine
> : them.  you might try this (note the \makeat...
> : commands needed since there is an @ in the name):
> :
> : \makeatletter
> :   \bigskipamount.7\baselineskip plus.7\baselineskip
> :   \medskipamount\bigskipamount \divide\medskipamount\tw@
> :   \smallskipamount\medskipamount \divide\smallskipamount\tw@
> :   \abovedisplayskip\smallskipamount  %%% cut in half
> :   \belowdisplayskip \abovedisplayskip
> :   \abovedisplayshortskip\abovedisplayskip
> :   \belowdisplayshortskip\abovedisplayshortskip
> :   \jot\baselineskip \divide\jot 4 \relax
> : }
> : \makeatother
> :
> : with 10pt type on 12pt baselines, \bigskipamount will
> : be about 8.5pt.  \medskipamount is half that (4.2pt)
> : and \smallskipamount half again (2.1pt).  there will
> : be an equal amount of stretch -- which is often the
> : only way to achieve a vertically justified page.
> :
> : if you want to get rid of the stretch (this will have
> : possibly unpleasant consequences elsewhere, e.g. between
> : paragraphs and before (sub)section headings), you can
> : set the displayskips to be a fixed value, such as
> :   \abovedisplayskip 2pt \relax
> : the \relax is needed to keep tex from looking ahead
> : for a stretch value, which is assumed for every skip.
> : 							-- bb
> :
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