delim $$
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EQN(1) GENIX Programmer's Manual EQN(1)
NAME
eqn, neqn, checkeq - typeset mathematics
SYNOPSIS
eqn [ -dxy ] [ -pn ] [ -sn ] [ -fn ] [ file ] ...
checkeq [ file ] ...
DESCRIPTION
Eqn is a troff(1) preprocessor for typesetting mathematics on a
Graphic Systems phototypesetter, neqn on terminals. Usage is almost
always
eqn file ... | troff
neqn file ... | nroff
If no files are specified, these programs reads from the standard
input. A line beginning with `.EQ' marks the start of an equation;
the end of an equation is marked by a line beginning with `.EN'.
Neither of these lines is altered, so they may be defined in macro
packages to get centering, numbering, etc. It is also possible to
set two characters as `delimiters'; subsequent text between delim-
iters is also treated as eqn input. Delimiters may be set to char-
acters x and y with the command-line argument -dxy or (more com-
monly) with `delim xy' between .EQ and .EN. The left and right del-
imiters may be identical. Delimiters are turned off by `delim off'.
All text that is neither between delimiters nor between .EQ and .EN
is passed through untouched.
The program checkeq reports missing or unbalanced delimiters and
.EQ/.EN pairs.
Tokens within eqn are separated by spaces, tabs, newlines, braces,
double quotes, tildes or circumflexes. Braces {} are used for
grouping; generally speaking, anywhere a single character like x
could appear, a complicated construction enclosed in braces may be
used instead. Tilde ~ represents a full space in the output, cir-
cumflex ^ half as much.
Subscripts and superscripts are produced with the keywords sub and
sup. Thus x sub i makes $x sub i$, a sub i sup 2 produces $a sub i
sup 2$, and e sup {x sup 2 + y sup 2} gives $e sup {x sup 2 + y sup
2}$.
Fractions are made with over: a over b yields $a over b$.
sqrt makes square roots: 1 over sqrt {ax sup 2 +bx+c} results in $1
over sqrt {ax sup 2 +bx+c}$ .
The keywords from and to introduce lower and upper limits on arbi-
trary things: $lim from {n-> inf} sum from 0 to n x sub i$ is made
with lim from {n-> inf } sum from 0 to n x sub i.
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EQN(1) GENIX Programmer's Manual EQN(1)
Left and right brackets, braces, etc., of the right height are made
with left and right: left [ x sup 2 + y sup 2 over alpha right ]
~=~1 produces $left [ x sup 2 + y sup 2 over alpha right ] ~=~1$.
The right clause is optional. Legal characters after left and right
are braces, brackets, bars, c and f for ceiling and floor, and ""
for nothing at all (useful for a right-side-only bracket).
Vertical piles of things are made with pile, lpile, cpile, and
rpile: pile {a above b above c} produces $pile {a above b above c}$.
There can be an arbitrary number of elements in a pile. lpile
left-justifies, pile and cpile center, with different vertical spac-
ing, and rpile right justifies.
Matrices are made with matrix: matrix { lcol { x sub i above y sub 2
} ccol { 1 above 2 } } produces $matrix { lcol { x sub i above y sub
2 } ccol { 1 above 2 } }$. In addition, there is rcol for a right-
justified column.
Diacritical marks are made with dot, dotdot, hat, tilde, bar, vec,
dyad, and under: x dot = f(t) bar is $x dot = f(t) bar$, y dotdot
bar ~=~ n under is $y dotdot bar ~=~ n under$, and x vec ~=~ y dyad
is $x vec ~=~ y dyad$.
Sizes and font can be changed with size n or size +n, roman, italic,
bold, and font n. Size and fonts can be changed globally in a docu-
ment by gsize n and gfont n, or by the command-line arguments -sn
and -fn.
Normally subscripts and superscripts are reduced by 3 point sizes
from the previous size; this may be changed by the command-line
argument -pn.
Successive display arguments can be lined up. Place mark before the
desired lineup point in the first equation; place lineup at the
place that is to line up vertically in subsequent equations.
Shorthands may be defined or existing keywords redefined with
define: define thing % replacement % defines a new token called
thing which will be replaced by replacement whenever it appears
thereafter. The % may be any character that does not occur in
replacement.
Keywords like sum ( sum ) int ( int ) inf ( inf ) and shorthands
like >= (>=) -> (->), and != ( != ) are recognized. Greek letters
are spelled out in the desired case, as in alpha or GAMMA. Mathemat-
ical words like sin, cos, log are made Roman automatically.
Troff(1) four-character escapes like \(bs () can be used anywhere.
Strings enclosed in double quotes "..." are passed through
untouched; this permits keywords to be entered as text, and can be
used to communicate with troff when all else fails.
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EQN(1) GENIX Programmer's Manual EQN(1)
SEE ALSO
troff(1), tbl(1), ms(7), eqnchar(7)
B. W. Kernighan and L. L. Cherry, Typesetting Mathematics-User's
Guide
J. F. Ossanna, NROFF/TROFF User's Manual
BUGS
To embolden digits, parens, etc., it is necessary to quote them, as
in `bold "12.3"'.
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