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Figure 1.  Example of a Floating Keep.
.hl
.)z
The
.b .hl
request is used
to draw a horizontal line
so that the figure
stands out from the text.
.sh 2 "Fancier Displays"
.pp
Keeps and lists are normally collected in
.i nofill
mode,
so that they are good for tables and such.
If you want a display
in fill mode
(for text),
type
.b ".(l\ F"
(Throughout this section,
comments applied to
.b .(l
also apply to
.b .(b
and
.b .(z ).
This kind of display
will be indented from both margins.
For example,
the input:
.(b
\&.(l F
And now boys and girls,
a newer, bigger, better toy than ever before!
Be the first on your block to have your own computer!
Yes kids, you too can have one of these modern
data processing devices.
You too can produce beautifully formatted papers
without even batting an eye!
\&.)l
.)b
will be output as:
.(b F
And now boys and girls,
a newer, bigger, better toy than ever before!
Be the first on your block to have your own computer!
Yes kids, you too can have one of these modern
data processing devices.
You too can produce beautifully formatted papers
without even batting an eye!
.)b
.pp
Lists and blocks are also normally indented
(floating keeps are normally left justified).
To get a left-justified list,
type
.b ".(l\ L" .
To get a list centered
line-for-line,
type
.b ".(l C" .
For example,
to get a filled,
left justified list, enter:
.(b
\&.(l L F
text of block
\&.)l
.)b
The input:
.(b
\&.(l
first line of unfilled display
more lines
\&.)l
.)b
produces the indented text:
.(b
first line of unfilled display
more lines
.)b
Typing the character
.b L
after the
.b .(l
request produces the left justified result:
.(b L
first line of unfilled display
more lines
.)b
Using
.b C
instead of
.b L
produces the line-at-a-time centered output:
.(b C
first line of unfilled display
more lines
.)b
.pp
Sometimes it may be
that you want to center several lines
as a group,
rather than centering them
one line at a time.
To do this
use centered blocks,
which are surrounded by the requests
.b .(c
and
.b .)c .
All the lines are centered as a unit,
such that the longest line is centered
and the rest are
lined up around that line.
Notice that lines
do not move
relative to each other
using centered blocks,
whereas they do
using the
.b C
argument to keeps.
.pp
Centered blocks are
.i not
keeps,
and may be used
in conjunction
with keeps.
For example,
to center a group of lines
as a unit
and keep them
on one page,
use:
.(b
\&.(b L
\&.(c
first line of unfilled display
more lines
\&.)c
\&.)b
.)b
to produce:
.(b L
.(c
first line of unfilled display
more lines
.)c
.)b
If the block requests
(\c
.b .(b
and
.b .)b )
had been omitted
the result would have been the same,
but with no guarantee
that the lines of the centered block
would have all been on one page.
Note the use of the
.b L
argument to
.b .(b ;
this causes the centered block
to center within the entire line
rather than within the line
minus the indent.
Also,
the center requests
must
be nested
.i inside
the keep requests.
.sh 1 "Annotations"
.pp
There are a number of requests
to save text
for later printing.
.i Footnotes
are printed at the bottom of the current page.
.i "Delayed text"
is intended to be a variant form
of footnote;
the text is printed only 
when explicitly called for,
such as at the end of each chapter.
.i Indexes
are a type of delayed text
having a tag
(usually the page number)
attached to each entry
after a row of dots.
Indexes are also saved
until called for explicitly.
.sh 2 "Footnotes"
.pp
Footnotes begin with the request
.b .(f
and end with the request
.b .)f .
The current footnote number is maintained
automatically,
and can be used by typing \e**,
to produce a footnote number\**.
.(f
\**Like this.
.)f
The number is automatically incremented
after every footnote.
For example,
the input:
.(b
\&.(q
A man who is not upright
and at the same time is presumptuous;
one who is not diligent and at the same time is ignorant;
one who is untruthful and at the same time is incompetent;
such men I do not count among acquaintances.\e**
\&.(f
\e**James R. Ware,
\&.ul
The Best of Confucius,
Halcyon House, 1950.
Page 77.
\&.)f
\&.)q
.)b
generates the result:
.(q
A man who is not upright
and at the same time is presumptuous;
one who is not diligent and at the same time is ignorant;
one who is untruthful and at the same time is incompetent;
such men I do not count among acquaintances.\**
.(f
\**James R. Ware,
.ul
The Best of Confucius,
Halcyon House, 1950.
Page 77.
.)f
.)q
It is important
that the footnote
appears
.i inside
the quote,
so that you can be sure
that the footnote
will appear
on the same page
as the quote.
.sh 2 "Delayed Text"
.pp
Delayed text
is very similar to a footnote
except that it is printed
when called for explicitly.
This allows a list of
references to
appear
(for example)
at the end of each chapter,
as is the convention in some disciplines.
Use
.b \e*#
on delayed text
instead of
.b \e**
as on footnotes.
.pp
If you are using delayed text
as your standard reference mechanism,
you can still use footnotes,
except that you may want to reference them
with special characters*
.(f
*Such as an asterisk.
.)f
rather than numbers.
.sh 2 "Indexes"
.pp
An
.q index
(actually more like a table of contents,
since the entries are not sorted alphabetically)
resembles delayed text,
in that it is saved until called for.
However,
each entry has the page number
(or some other tag)
appended to the last line
of the index entry
after a row of dots.
.pp
Index entries begin with the request
.b .(x
and end with
.b .)x .
The
.b .)x
request may have a argument,
which is the value to print
as the
.q "page number" .
It defaults to the current page number.
If the page number given is an underscore
(\c
.q _ )
no page number
or line of dots
is printed at all.
To get the line of dots
without a page number,
type
.b ".)x """"" ,
which specifies an explicitly null page number.
.pp
The
.b .xp
request prints the index.
.pp
For example,
the input:
.(b
\&.(x
Sealing wax
\&.)x
\&.(x
Cabbages and kings
\&.)x _
\&.(x
Why the sea is boiling hot
\&.)x 2.5a
\&.(x
Whether pigs have wings
\&.)x ""
\&.(x
This is a terribly long index entry, such as might be used
for a list of illustrations, tables, or figures; I expect it to
take at least two lines.
\&.)x
\&.xp
.)b
generates:
.(x
Sealing wax
.)x
.(x
Cabbages and kings
.)x _
.(x
Why the sea is boiling hot
.)x 2.5a
.(x
Whether pigs have wings
.)x ""
.(x
This is a terribly long index entry, such as might be used
for a list of illustrations, tables, or figures; I expect it to
take at least two lines.
.)x
.xp
.pp
The
.b .(x
request may have a single character
argument,
specifying the
.q name
of the index;
the normal index is
.b x .
Thus,
several
.q indices
may be maintained simultaneously
(such as a list of tables, table of contents, etc.).
.pp
Notice that the index must be printed
at the
.i end
of the paper,
rather than at the beginning
where it will probably appear
(as a table of contents);
the pages may have to be physically rearranged
after printing.
.sh 1 "Fancier Features"
.pp
A large number of fancier requests
exist,
notably requests to provide other sorts of paragraphs,
numbered sections of the form
.b 1.2.3
(such as used in this document),
and multicolumn output.
.sh 2 "More Paragraphs"
.pp
Paragraphs generally start with
a blank line
and with the first line
indented.
It is possible to get
left-justified block-style paragraphs
by using
.b .lp
instead of
.b .pp ,
as demonstrated by the next paragraph.
.lp
Sometimes you want to use paragraphs
that have the
.i body
indented,
and the first line
exdented
(opposite of indented)
with a label.
This can be done with the
.b .ip
request.
A word specified on the same line as
.b .ip
is printed in the margin,
and the body is lined up
at a prespecified position
(normally five spaces).
For example,
the input:
.(b
\&.ip one
This is the first paragraph.
Notice how the first line
of the resulting paragraph lines up
with the other lines in the paragraph.
\&.ip two
And here we are at the second paragraph already.
You may notice that the argument to \c
.b .ip
appears
in the margin.
\&.lp
We can continue text...
.)b
produces as output:
.ip one
This is the first paragraph.
Notice how the first line of the resulting paragraph lines up
with the other lines in the paragraph.
.ip two
And here we are at the second paragraph already.
You may notice that the argument to
.b .ip
appears
in the margin.
.lp
We can continue text without starting a new indented
paragraph
by using the
.b .lp
request.
.pp
If you have spaces in the label of a
.b .ip
request,
you must use an
.q "unpaddable space"
instead of a regular space.
This is typed as a backslash character
(\c
.q \e )
followed by a space.
For example,
to print the label
.q "Part 1" ,
enter:
.(b
\&.ip "Part\e 1"
.)b
.pp
If a label of an indented paragraph
(that is, the argument to
.b .ip )
is longer than the space allocated for the label,
.b .ip
will begin a new line after the label.
For example,
the input:
.(b
\&.ip longlabel
This paragraph had a long label.
The first character of text on the first line
will not line up with the text on second and subsequent lines,
although they will line up with each other.
.)b
will produce:
.ip longlabel
This paragraph had a long label.
The first character of text on the first line
will not line up with the text on second and subsequent lines,
although they will line up with each other.
.pp
It is possible to change the size of the label
by using a second argument
which is the size of the label.
For example,
the above example could be done correctly
by saying:
.(b
\&.ip longlabel 10
.)b
which will make the paragraph indent
10 spaces for this paragraph only.
If you have many paragraphs to indent
all the same amount,
use the
.i "number register"
.b ii .
For example, to leave one inch of space
for the label,
type:
.(b
\&.nr ii 1i
.)b
somewhere before the first call to
.b .ip .
Refer to the reference manual
for more information.
.pp
If
.b .ip
is used
with no argument at all
no hanging tag will be printed.
For example,
the input:
.(b
\&.ip [a]
This is the first paragraph of the example.
We have seen this sort of example before.
\&.ip
This paragraph is lined up with the previous paragraph,
but it has no tag in the margin.
.)b
produces as output:
.ip [a]
This is the first paragraph of the example.
We have seen this sort of example before.
.ip
This paragraph is lined up with the previous paragraph,
but it has no tag in the margin.
.pp
A special case of
.b .ip
is
.b .np ,
which automatically
numbers paragraphs sequentially from 1.
The numbering is reset at the next
.b .pp ,
.b .lp ,
or
.b .sh
(to be described in the next section)
request.
For example,
the input:
.(b
\&.np
This is the first point.
\&.np
This is the second point.
Points are just regular paragraphs
which are given sequence numbers automatically
by the .np request.
\&.pp
This paragraph will reset numbering by .np.
\&.np
For example,
we have reverted to numbering from one now.
.)b
generates:
.np
This is the first point.
.np
This is the second point.
Points are just regular paragraphs
which are given sequence numbers automatically
by the .np request.
.pp
This paragraph will reset numbering by .np.
.np
For example,
we have reverted to numbering from one now.
.pp
The
.b .bu
request gives lists of this sort that are identified with
bullets rather than numbers.
The paragraphs are also crunched together.
For example,
the input:
.(b
\&.bu
\&One egg yolk
\&.bu
\&One tablespoon cream or top milk
\&.bu
\&Salt, cayenne, and lemon juice to taste
\&.bu
\&A generous two tablespoonfuls of butter
.)b
produces\**:
.(f
\**By the way,
if you put the first three ingredients in a a heavy, deep pan
and whisk the ingredients madly over a medium flame
(never taking your hand off the handle of the pot)
until the mixture reaches the consistency of custard
(just a minute or two),
then mix in the butter off-heat,
you will have a wonderful Hollandaise sauce.
.)f
.bu
One egg yolk
.bu
One tablespoon cream or top milk
.bu
Salt, cayenne, and lemon juice to taste
.bu
A generous two tablespoonfuls of butter
.sh 2 "Section Headings"
.pp
Section numbers
(such as the ones used in this document)
can be automatically generated
using the
.b .sh
request.
You must tell
.b .sh
the
.i depth
of the section number
and a section title.
The depth
specifies how many numbers
are to appear
(separated by decimal points)
in the section number.
For example,
the section number
.b 4.2.5
has a depth of three.
.pp
Section numbers
are incremented
in a fairly intuitive fashion.
If you add a number
(increase the depth),
the new number starts out
at one.
If you subtract section numbers
(or keep the same number)
the final number is incremented.
For example,
the input:
.(b
\&.sh 1 "The Preprocessor"
\&.sh 2 "Basic Concepts"
\&.sh 2 "Control Inputs"
\&.sh 3
\&.sh 3
\&.sh 1 "Code Generation"
\&.sh 3
.)b
produces as output the result:
.(b
.b
1.  The Preprocessor
1.1.  Basic Concepts
1.2.  Control Inputs
1.2.1.
1.2.2.
2.  Code Generation
2.1.1.
.)b
.pp
You can specify the section number to begin
by placing the section number after the section title,
using spaces instead of dots.
For example,
the request:
.(b
\&.sh 3 "Another section" 7 3 4
.)b
will begin the section numbered
.b 7.3.4 ;
all subsequent
.b .sh
requests will number relative to this number.
.pp
There are more complex features
which will cause each section to be indented
proportionally to the depth of the section.
For example, if you enter:
.(b
\&.nr si \c
.i N
.)b
each section will be indented by an amount
.i N .
.i N
must have a scaling factor attached,
that is, it must be of the form
.i Nx ,
where
.i x
is a character telling what units
.i N
is in.
Common values for
.i x
are
.b i
for inches,
.b c
for centimeters,
and
.b n
for
.i ens
(the width of a single character).
For example,
to indent each section
one-half inch,
type:
.(b
\&.nr si 0.5i
.)b
After this,
sections will be indented by
one-half inch