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.\" to Deri James for PDF support.
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.TL
Typesetting Mathematics _ User's Guide
\&\ \ \ \ \ (Second\ Edition)
.AU 2C-518 6021
Brian W. Kernighan and Lorinda L. Cherry
.AI
.MH
.AB
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.pdfinfo /Title Typesetting Mathematics - User's Guide (Second Edition)
.pdfinfo /Author Brian W. Kernighan and Lorinda L. Cherry
.PP
This is the user's guide for a system for typesetting
mathematics,
using
the \%photo\%typesetters on the
.UX
and
.UC GCOS
operating systems.
.PP
Mathematical expressions are described in a language
designed to be easy to use
by people who know neither mathematics nor typesetting.
Enough of the language to set in-line expressions like
.\" Correct missing space before "->" for GNU eqn.  GBR, 2022.
$lim from {x -> pi /2} ( tan~x) sup{sin~2x}~=~1$
or display equations like
.\"in .5i
.EQ I
G(z)~mark =~ e sup { ln ~ G(z) }
~=~ exp left ( 
sum from k>=1 {S sub k z sup k} over k right )
~=~  prod from k>=1 e sup {S sub k z sup k /k}
.EN
.\" Use "cdots" for ellipses on the math axis; "ldots" on the baseline.
.\" Redefine them to space them more widely.  Use ~ more generously than
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.EQ I
define cdots "{ \[md]~\[md]~\[md] }"
define ldots "{ .~.~. }"
lineup = left ( 1 + S sub 1 z + 
{ S sub 1 sup 2 z sup 2 } over 2! + ~ cdots right )
~ left ( 1+ { S sub 2 z sup 2 } over 2
+ { S sub 2 sup 2 z sup 4 } over { 2 sup 2 cdot 2! }
+ ~ cdots right ) ~ cdots
.EN
.EQ I
lineup =  sum from m>=0 left (
sum from
pile { k sub 1 ,k sub 2 , ~ ldots ~ , k sub m  >=0
above
k sub 1 +2k sub 2 + ~ cdots ~ +mk sub m =m}
{ S sub 1 sup {k sub 1} } over {1 sup k sub 1 k sub 1 ! } ~
{ S sub 2 sup {k sub 2} } over {2 sup k sub 2 k sub 2 ! } ~
cdots
{ S sub m sup {k sub m} } over {m sup k sub m k sub m ! } 
right ) ~ z sup m
.EN
.\"in 0
can be learned in an hour or so.
.PP
The language interfaces directly with
the phototypesetting language
.UC TROFF ,
so mathematical expressions can be embedded in the running
text
of a manuscript,
and the entire document produced in one process.
This user's guide is an example of its output.
.PP
The same language
may be used with the 
.UC UNIX
formatter
.UC NROFF
to set mathematical \%expressions on
.UC DASI
and
.UC GSI
terminals
and Model 37 teletypes.
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.AE
.\"CS 11 0 11 0 0 3