.lm
.ifnot hlp
.lm.hl 1 Equation formatting
.else hlp
.helpb equations
.endif hlp
.f.p
This feature is not available in DSR. An equation formatting routine has been
added to RUNOFF.  This is designed to format multiple nested fractions.  To
use this facility the equation flag must be enabled via the _.FLAGS EQUATION
command. Subscripts or superscripts are normally taken care of in formatting
fractions, but you may wish to add extra space between the line and the
numerator or denominator.  To do this give the command _.ENABLE EQUATION 1 to
add 1/2 line or _.ENABLE EQUATION 2 to add 1 whole line. With these
preliminary commands out of the way the braces _{ _} are now flags which are
used in formatting equations.  They must be preceeded by the underscore __ if
they are to appear in the text. 
.p.text
Fractions are formatted in the following manner.  You express the faction as:
.i10; {NUMERATOR}/{DENOMINATOR}
.br;and RNO will output:
.nf.lm+10; NUMERATOR
______________________
DENOMINATOR
.end text
.f.lm-10
.if HLP
.if RSX.ts 25,45,55.nj
Subtopics available:
.s;note	features nesting	spacing	vertical__spacing
	warning	commands
.j
.endif RSX
.endif hlp
.helpc note
.p
Some operating systems do strange things to the output, so if you are unable
to get equations to work correctly try using the /TT switch and having
RNO output the text directly to the printer.  In particular VMS swallows
some of the backspaces so the output is not correct!
.helpc features
.p;Inside an equation the following features are disabled:
.list0.le Underline flags
.le Fill
.le Underlining
.le Break flags - No break is caused, but lines may be continued.
.le Hyphenation - Hyphenation flags may be used to continue a line.
.le Autobreak
.le Tabs
.els 0
.helpc  Nesting
.tp3.p
Fractions may be nested inside each other.
.i5;For example {{A}/{B}#+#{C}/{D}}/{DENOMINATOR}.
.i5;A/B and C/D are both nested to the second level.
.br;The maximum nesting is about 6 deep.  If the nesting is all in numerators
then
it is limited to 12, all in denominators is limited to 6.
.p.i5;Example of 4 levels of nesting in numerators:
.i5;{1+{2+{3+{4}/{D}}/{C}}/{B}}/{A}
.i5;Example of 6 levels of nesting in denominators:
.p.i5;{1}/{A+ {2}/{B+{3}/{C+{4}/{D+{5}/{E+{6}/{F}}}}}}
.helpc  Spacing
.p
Spaces or tabs may be freely used between numerators and denominators outside
of the braces for clarity.  They will not appear in the final output.
For example {A}/{B} will format the same as {A}#/#{B}.
In addition tabs and spaces are all treated as non expandable spaces.
As a result fractions are never expanded to right justify the text.
If an equation is imbedded inside a normal line of text and Fill is enabled,
only the text outside the equation is filled.
The commands _.CENTER and _.RIGHT will center or right justify equations.
In addition centered and right justified tab stops can be used to line
un equations.
.helpc  Vertical__spacing
.p
Fractions may occasionally occupy too much space to fit within
the current line spacing.  If this happens you should use the command
 _.SEPARATED FRACTION.
This mode automatically generates enough space to separate fractions.
If you prefer to manually adjust the spacing then
the _.FIGURE command should be used.
.p;You may wish to put equation numbers along the right margin next to
the equation.  This is accomplished by resetting the tab stops, and
setting tab right.  A single tab should preceed the number to be justified.
.text;The following example shows the commands necessary to do this:
.i5; _.TAB STOPS _.TAB RIGHT
.i5; {A + B}/{C + D}	eq.___#5
.c;Is printed as:
.i5;A + B
.tab stops .tab right.i5;__________	eq._#5
.i5;C + D
.end text.s.tab left
.helpc  WARNING
.note WARNING
A Fraction may not be split between 2 output lines.
If a fraction imbedded in text is so big that it can not fit on the current
line, it is moved down to the next line.  If the fraction is still too big
then RNO will try to break it.  The break will most probably
result in the error message:
.c;RNO -- Missing right brace in equation
A string of other error messages will probably follow the first one
and the output text will usually look very strange.
The extra error messages should be ignored.  The solution to the problem
is to break the fraction up into 2 fractions.
A Fraction should not be split between more than 1 input line to prevent
RNO from breaking it.  If the fraction exceeds the input line capacity of
RNO you can split it if you are careful.
.end note
.helpc  Commands
.p
The commands used to control equation formatting are:
.list 0
.le _.FLAGS EQUATION
.le _.NO FLAGS EQUATION
.le _.ENABLE EQUATION n
.LE _.DISABLE EQUATION
.le _.SEPARATED EQUATION
.le _.END SEPARATED EQUATION
.END LIST
.note
This equation routine will only work properly with word processing style hard
copy printers which support sub/superscript escape sequences and backspacing. 
In addition sub/superscripting escape sequences must be defined by the
_.DEFINE SUBSCRIPT and _.DEFINE SUPERSCRIPT commands if they are not the same
as used by DIABLO printers. In addition the paper must not slip when
superscripting is performed.  Some printers with cut sheet feeders allow the
paper to slip which produces unacceptable output.  Equations inside titles or
subtitles could cause problems if the top margin is not big enough. 
.end note