Texinfo provides several commands for formatting dimensions, for inserting single characters that have special meaning in Texinfo, such as braces, and for inserting special graphic symbols that do not correspond to characters, such as dots and bullets.
These are:
`@' and curly braces are special characters in Texinfo. To insert these characters so they appear in text, you must put an `@' in front of these characters to prevent Texinfo from misinterpreting them.
Periods are also special. Depending on whether the period is inside or at the end of a sentence, less or more space is inserted after a period in a typeset manual. Since it is not always possible for Texinfo to determine when a period ends a sentence and when it is used in an abbreviation, special commands are needed in some circumstances. (Usually, Texinfo can guess how to handle periods, so you do not need to use the special commands; you just enter a period as you would if you were using a typewriter, which means you put two spaces after the period, question mark, or exclamation mark that ends a sentence.)
Do not put braces after any of these commands; they are not necessary.
@@ stands for a single `@' in either printed or Info
output.
Do not put braces after an @@ command.
@{ stands for a single `{' in either printed or Info
output.
@} stands for a single `}' in either printed or Info
output.
Do not put braces after either an @{ or an @}
command.
Use the @: command after a period, question mark,
exclamation mark, or colon that should not be followed by extra space.
For example, use @: after periods that end abbreviations
which are not at the ends of sentences. @: has no effect on
the Info file output.
For example,
The s.o.p.@: has three parts ... The s.o.p. has three parts ...
produces the following. If you look carefully at this printed output, you will see a little more whitespace after `s.o.p.' in the second line.
The s.o.p. has three parts ...
The s.o.p. has three parts ...
@: has no effect on the Info output. (`s.o.p' is an acronym for "Standard Operating Procedure".)
Use @. instead of a period at the end of a sentence that
ends with a single capital letter. Otherwise, TeX will think the
letter is an abbreviation and will not insert the correct
end-of-sentence spacing. Here is an example:
Give it to M.I.B. and to M.E.W@. Also, give it to R.J.C@. Give it to M.I.B. and to M.E.W. Also, give it to R.J.C.
produces the following. If you look carefully at this printed output, you will see a little more whitespace after the `W' in the first line.
Give it to M.I.B. and to M.E.W. Also, give it to R.J.C.
Give it to M.I.B. and to M.E.W. Also, give it to R.J.C.
In the Info file output, @. is equivalent to a simple
`.'.
The meanings of @: and @. in Texinfo are designed
to work well with the Emacs sentence motion commands. This made it
necessary for them to be incompatible with some other formatting
systems that use @-commands.
Do not put braces after either an @: or an @. command.
@dmn{dimension}: Format a Dimension
At times, you may want to write `12pt' or
`8.5in' with little or no space between the number and the
abbreviation for the dimension. You can use the @dmn command
to do this. On seeing the command, TeX inserts just enough space
for proper typesetting; the Info formatting commands insert no space
at all, since the Info file does not require it.
To use the @dmn command, write the number and then follow it
immediately, with no intervening space, by @dmn, and then by
the dimension within braces.
For example,
A4 paper is 8.27@dmn{in} wide.
produces
A4 paper is 8.27in wide.
Not everyone uses this style. Instead of writing `8.27@dmn{in}' in the Texinfo file, you may write `8.27 in.' or `8.27 inches'. (In these cases, the formatters may insert a line break between the number and the dimension. Also, if you write a period after an abbreviation within a sentence, you should write `@:' after the period to prevent TeX from inserting extra whitespace. See section Spacing After Colons and Periods.)
An ellipsis (a line of dots) is not typeset as a string of
periods, so a special command is used for ellipsis in Texinfo. The
@bullet command is special, too. Each of these commands is
followed by a pair of braces, `{}', without any whitespace
between the name of the command and the braces. (You need to use braces
with these commands because you can use them next to other text; without
the braces, the formatters would be confused. See section @-Command Syntax, for further information.)
@dots{}
Use the @dots{} command to generate an ellipsis, which is
three dots in a row, appropriately spaced, like this: `...'. Do
not simply write three periods in the input file; that would work for
the Info file output, but would produce the wrong amount of space
between the periods in the printed manual.
Similarly, the @enddots{} command helps you correctly set an
end-of-sentence ellipsis (four dots).
Here is an ellipsis: ...
Here are three periods in a row: ...
In printed output, the three periods in a row are closer together than the dots in the ellipsis.
@bullet{}
Use the @bullet{} command to generate a large round dot, or
the closest possible thing to one. In Info, an asterisk is used.
Here is a bullet: *
When you use @bullet in @itemize, you do not need to
type the braces, because @itemize supplies them.
(See section Making an Itemized List.)
The logo `TeX' is typeset in a special fashion and it needs an @-command. The copyright symbol, `(C)', is also special. Each of these commands is followed by a pair of braces, `{}', without any whitespace between the name of the command and the braces.
@copyright{}.
@TeX{}
Use the @TeX{} command to generate `TeX'. In a printed
manual, this is a special logo that is different from three ordinary
letters. In Info, it just looks like `TeX'. The
@TeX{} command is unique among Texinfo commands in that the
T and the X are in upper case.
@copyright{}
Use the @copyright{} command to generate `(C)'. In
a printed manual, this is a `c' inside a circle, and in Info,
this is `(C)'.
@minus{}: Inserting a Minus Sign
Use the @minus{} command to generate a minus sign. In a
fixed-width font, this is a single hyphen, but in a proportional font,
the symbol is the customary length for a minus sign--a little longer
than a hyphen.
You can compare the two forms:
`-' is a minus sign generated with `@minus{}',
`-' is a hyphen generated with the character `-'.
In the fixed-width font used by Info, @minus{} is the same
as a hyphen.
You should not use @minus{} inside @code or
@example because the width distinction is not made in the
fixed-width font they use.
When you use @minus to specify the mark beginning each entry in
an itemized list, you do not need to type the braces
(see section Making an Itemized List.)
@math: Inserting Mathematical Expressions
You can write a short mathematical expression with the @math
command. Write the mathematical expression between braces, like this:
@math{(a + b)(a + b) = a^2 + 2ab + b^2}
This produces the following in TeX:
@math{(a + b)(a + b) = a^2 + 2ab + b^2}
and the following in Info:
(a + b)(a + b) = a^2 + 2ab + b^2
The @math command has no effect on the Info output. Currently,
it has limited effect on typeset output. However, this may change since
TeX itself is designed for mathematical typesetting and does a
splendid job.
Certainly, for complex mathematical expressions, you could use TeX directly. See section Using Ordinary TeX Commands. When you use TeX directly, remember to write the mathematical expression between one or two `$' (dollar-signs) as appropriate.