eqn(1) UNIX System V(BSD Compatibility Package) eqn(1)
NAME
eqn, neqn, checkeq - typeset mathematics
SYNOPSIS
/usr/ucb/eqn [ -dxy ] [ -fn ] [ -pn ] [ -sn ] [ filename ] . . .
/usr/ucb/neqn [ filename ] . . .
/usr/ucb/checkeq [ filename ] . . .
DESCRIPTION
The eqn and neqn commands are language processors to assist in describing
equations. eqn is a preprocessor for troff(1) and is intended for
devices that can print troff's output. neqn is a preprocessor for
nroff(1) and is intended for use with terminals.
checkeq reports missing or unbalanced delimiters and .EQ/.EN pairs.
If no filenames are specified, eqn and neqn read 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 delimiters is also treated as eqn
input.
The following options are available for eqn and neqn:
-dxy Set equation delimiters set to characters x and y with the
command-line argument. The more common way to do this is with
delimxy between .EQ and .EN. The left and right delimiters may be
identical. Delimiters are turned off by delim off appearing in the
text. All text that is neither between delimiters nor between .EQ
and .EN is passed through untouched.
-fn Change font to n globally in the document. The font can also be
changed globally in the body of the document by using the gfont
directive.
-pn Reduce subscripts and superscripts by n point sizes from the
previous size. In the absence of the -p option, subscripts and
superscripts are reduced by 3 point sizes from the previous size.
-sn Set equations in point size n globally in the document. The point
size can also be changed globally in the body of the document by
using the gsize directive.
-Tdev Prepare output for device dev. If no -T option is present, eqn
looks at the environment variable TYPESETTER to see what the
intended output device is. If no such variable is found in the
environment, a system-dependent default device is assumed. Not
available using neqn.
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eqn(1) UNIX System V(BSD Compatibility Package) eqn(1)
USAGE
eqn Language
Tokens within eqn are separated by braces, double quotes, tildes,
circumflexes, SPACE, TAB, or NEWLINE characters. 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, circumflex (^)
half as much.
Subscripts and superscripts are produced with the key2
w,
ora
dn
sdsub sup supsup
2h+sy`xusub}i'gi
ma
ve
ke
ssex2
x+
iy,
2.`a sub i sup 2' produces ai
a.
Fractions are made with over: `a over b' yields b
sqrt makes square roots: `1 over down 10 sqrt {ax sup 2 +bx+c}' results
in
_____1____.
________
\|ax2+bx+c
Although eqn tries to get most things at the right place on the paper,
occasionally you will need to tune the output to make it just right. In
the previous example, a local motion, down 10 was used to get more space
between the square root and the line above it.
The keywords from and to introduce lower and upper limits on arbitrary
things: lim ≳xi is made with `lim from {n-> inf } sum from 0 to n x sub
i'. n->oo0
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 |
| y2| = 1.
|x2+α |
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 wia
th pile, lpile, cpile, and rpile:
`pile {a above b above c}' produces b. There can be an arbitrary number
of elements in a pile. lpile left-juc
stifies, pile and cpile center, with
different vertical spacing, and rpile right justifies.
Matrices are made with matrix: `matrix { lcol { x sub i above y sub 2 }
ccol { 1 above 2 } }' produces xi
y2
1
2
. In addition, there is rcol for a
right-justified column.
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eqn(1) UNIX System V(BSD Compatibility Package) eqn(1)
Diacritical marks are made with dot,_dotdot, hat, tilde, bar, vec, dyad,
.
a.
nd under: `x dot = f(t) bar' is x=f(t), `y dotdot bar ~=~ n under' is
y = n, and `x vec ~=~ y dyad' is x = y.
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 document
by gsize n and gfont n, or by the command-line arguments -sn and -fn.
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 (≳), int (∫), inf (oo), and shorthands like >= (>), ->
(->), and != (≠) are recognized. Greek letters are spelled out in the
desired case, as in alpha or GAMMA. Mathematical words like sin, cos,
and log are made Roman automatically. troff(1) four-character escapes
like \(bu (⊕) 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.
EXAMPLE
eqn filename . . . | troff
neqn filename . . . | nroff
SEE ALSO
tbl(1), troff(1), eqnchar(7), ms(7)
NOTES
To embolden digits, parens, etc., it is necessary to quote them, as in
bold "12.3".
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