eqn(1) User Commands eqn(1)
NAME
eqn, neqn, checkeq  typeset mathematics test
SYNOPSIS
eqn [d xy] [f n] [p n] [s n] [file...]
neqn [file...]
checkeq [file...]
DESCRIPTION
eqn and neqn 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. Usage is almost always:
example% eqn file ...  troff
example% neqn file ...  nroff
If no files 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, and so on. It is also possible to set two characters as
``delimiters''; subsequent text between delimiters is also treated as
eqn input.
checkeq reports missing or unbalanced delimiters and .EQ/.EN pairs.
OPTIONS
The following options are supported:
dxy Sets equation delimiters set to characters x and y with the
commandline argument. The more common way to do this is with
delim xy 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 delim
iters nor between .EQ and .EN is passed through untouched.
fn Changes font to n globally in the document. The font can also
be changed globally in the body of the document by using the
gfont n directive, where n is the font specification.
pn Reduces 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 previ
ous size.
sn Changes point size to n globally in the document. The point
size can also be changed globally in the body of the document
by using the gsize n directive, where n is the point size.
OPERANDS
The following operands are supported:
file The nroff or troff file processed by eqn or neqn.
EQN LANGUAGE
The nroff version of this description depicts the output of neqn to
the terminal screen exactly as neqn is able to display it. To see an
accurate depiction of the output, view the printed version of this
page.
Tokens within eqn are separated by braces, double quotes, tildes, cir
cumflexes, <<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. A tilde (~) represents a full <<SPACE>> in the output; a circum
flex (^) half as much.
Subscripts and superscripts:
These are produced with the keywords sub and sup.
x sub i makes xi
a sub i sup 2 produces ai **2
e sup {x sup 2 + y sup 2} gives e**x**2+y**2
Fractions:
Fractions are made with over.
a over b
yields
delim $$
$a over b$
Equation in the form of a over b.
Square Roots:
These are made with sqrt
1 over sqrt {ax sup 2 +bx+c}
results in
delim $$
$1 over sqrt {ax sup 2 +bx+c}$
Equation in the form 1 over the square root of ax squared plus bx plus
c
Limits:
The keywords from and to introduce lower and upper limits on arbitrary
things:
lim from {n>> inf } sum from 0 to n x sub i
makes
delim $$
$lim from {n> inf} sum from 0 to n x sub i$
Equation in the form lim from {n> inf } sum from 0 to n x sub i
Brackets and Braces:
Left and right brackets, braces, and the like, of the right height are
made with left and right.
left [ x sup 2 + y sup 2 over alpha right ] ~=~1
produces
delim $$
$left [ x sup 2 + y sup 2 over alpha right ] ~=~1$.
Equation in the form [ x sup 2 + y sup 2 over alpha ] = 1The 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 rightsideonly bracket).
Vertical piles:
Vertical piles of things are made with pile, lpile, cpile, and rpile.
pile {a above b above c}
produces
delim $$
$pile {a above b above c}$
Equation that shows a above b above cThere can be an arbitrary number
of elements in a pile. lpile leftjustifies, pile and cpile center,
with different vertical spacing, and rpile right justifies.
Matrices:
Matrices are made with matrix.
matrix { lcol { x sub i above y sub 2 } ccol { 1 above 2 } }
produces
delim $$
$matrix { lcol { x sub i above y sub 2 } ccol { 1 above 2 } }$
Matrix containing x sub i in above y sub 2 the left column and 1 above
2 in the right columnIn addition, there is rcol for a rightjustified
column.
Diacritical marks:
Diacritical marks are made with dot, dotdot, hat, tilde, bar, vec, dyad,
and under.
x dot = f(t) bar
is
delim $$
$x dot = f(t) bar$
Equation in the form x dot = f(t) bar
y dotdot bar ~=~ n under
is
delim $$
$y dotdot bar ~=~ n under$,
Equation in the form y dotdot bar = n under
x vec ~=~ y dyad
is
delim $$
$x vec ~=~ y dyad$.
Equation in the form x vec = y dyad
Sizes and Fonts:
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 commandline arguments sn and fn.
Successive display arguments:
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:
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 and Shorthands:
Keywords like sum int inf and shorthands like >>= >> and != are recognized.
Greek letters:
Greek letters are spelled out in the desired case, as in alpha or GAMMA.
Mathematical words:
Mathematical words like sin, cos, and log are made Roman automatically.
troff(1) fourcharacter escapes like \(bu (o) 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 commu
nicate with troff when all else fails.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
tab() allbox; cw(2.750000i) cw(2.750000i) lw(2.750000i)
lw(2.750000i). ATTRIBUTE TYPEATTRIBUTE VALUE AvailabilitySUNWdoc
SEE ALSO
nroff(1), tbl(1), troff(1), attributes(5), ms(5)
BUGS
To embolden characters such as digits and parentheses, it is necessary
to quote them, as in `bold "12.3"'.
SunOS 5.10 12 Jul 2002 eqn(1)
