Copyright © 1997-2000 by Uwe Böhme. This document may be distributed under the terms set forth in the Linux Documentation Project License at LDP. Please contact the authors if you are unable to get the license. This is free documentation. It is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.
This document is not part of ldp (even if I took their form of license). I'm not yet playing in that league.
This document was born trying to learn more about writing texts on my linux system. The one system looking like suitable to my needs was sgml-tools SGML-Tools Organsation an the linuxdoc dtd.
In [SGML-Tools User's Guide 1.0 ($Revision: 1.1.1.1 $)] (see section Reference) the overall structure is described nice and easy. Also [Quick SGML Example, v1.0] (see section Reference) was helpful, but:
A lot of features are not mentioned.
On the way to learn more about it, I met [The qwertz Document Type Definition] (see section Reference). It's as detailed as hoped, but it's not made for the linuxdoc dtd (even if linuxdoc is based on qwertz).
I tried a new approach: Look at the dtd
dtd = document type definitionfile itself, and try to understand it.
As time went by I noticed that I also forgot about some stuff, or - at least - didn't point it out strong enough. This will change within the next revision.
Any feedback you might have is welcome (especially help with English spelling or grammar) by e-mail at Uwe Böhme.
The principle of any sgml'ed document (linuxdoc, docbook, html) is more or less the same:
Don't write how it should look like, but write what it is.
This is a different approach than the standard "wysiwyg"
What you see is what you (should) get (if you are a very lucky one and your computer wins the war against buggy software)one
You might want to call it
wysiwym
, i.e. "What you see is what you mean"
.
You do not tell the program that this line should be in a bigger font,
to look like a headline.
What you do is telling that this line is a headline.
You do not try to make your document look like a
report, but you tag it to be a report.
So you tag the text with the appropriate <tag>.
The big advantages of this approache are:
If you ever tried the reuse a document written in a specialized wysiwy layout for html then you know what I'm talking about.
In addition in all sgml-style documents you will find named symbols This is a concept to expand the charset of the document and to avoid inconsitences in decision of the parser, how to interpret or map some special characters.
How should the parser know weather a <
character is
starting a tag or should be printed directly.
This is solved by the named character lt.
If you write <
this one will result to <
in your
text.
For a list of the named symbols see
Named Symbols.
It might be a good idea, to download this document not only as a dvi or ps document, but also to download the sgml source. This offers you the chance to look into the sources, if you find something within this article, wich might fit your needs.
In this section you'll find what you'll need for a minimalistic linuxdoc dtd conform document. It's intended to give a first touch. Skip this section, if you already now the principles.
The steps you have to do to create a nice linuxdoc document and map it to the form you need are:
start.sgml
.sgmlcheck start.sgml
.The error messages of sgmlcheck
will give you a hint about the type of error and also line and column where
it occurred.
.
Run the checker again until no more errors occur.
We start with a simple document (the numbers and colon in the beginning of the line are for explanation, don't type it!):
1: <!doctype linuxdoc system> 2: <notes> 3: <title>A Small Linuxdoc Example</title> 4: <p>Hello <em>world</em>.</p> 5: <p><bf>Here</bf> we are.</p> 6: </notes>
Now we take a look at the single lines:
<notes>
tag forming a note, wich is
indicating a simple unstructured document.
<title>
tag.
<p>
tag, containing the word world
wich is inline emphasized by the <em>
tag.
<bf>
tag.
The same example may be written a little bit shorter, by leaving out tags which are placed automatically by the parser, and by using shortened tags:
1: <!doctype linuxdoc system> 2: <notes> 3: <title>A Small Linuxdoc Example 4: <p>Hello <em/world/. 5: 6: <bf/Here/ we are. 7: </notes>
Now we look at the single lines again:
p
tag in the next line is
implicitely closing it.
/
. The paragraph is not explicitly
closed in this line.
Maybe now it's a little bit more clear, who you have to work with tags.
<!element linuxdoc o o (sect | chapt | article | report | book | letter | telefax | slides | notes | manpage ) >
This is describing the overall class of the document, so naturally it has
(leave alone the doctype definition) to be the first tag enclosing your whole
document.
Some of the tags namely the sect
and chapt
(see section
Sectioning Tags) doesn't make any sense taken them
standalone despite being included as part of more complete classed document,
so we'll describe them later as a part of the other document classes.
Decide first which of the top mentioned document classes fits the type of the
document you want to write best.
To find a detailed description of the document classes see table Document classes.
Chapter | Class tag |
Article Tag | <atricle> |
Report Tag | <report> |
Book Tag | <book> |
Letter Tag | <letter> |
Telefax Tag | <telefax> |
Slides Tag | <slides> |
Notes Tag | <notes> |
Manpage Tag | <manpage>
|
To me the article class is the most important one. Thatīs the reason why itīs described first and most detailed.
<!element article - - (titlepag, header?, toc?, lof?, lot?, p*, sect*, (appendix, sect+)?, biblio?) +(footnote)> <!attlist article opts cdata "null">
The options attribute (opts
) takes a comma separated list with thy
different style (LaTeX .sty
) sheets to inlude within the document.
<!element titlepag o o (title, author, date?, abstract?)>
titlepag
) is implicitly placed as soon a you
started your document class. You don't need to write it explicitly.
Anyway you have to note it's mandatory tags. It's purpouse is to describe the
layout and elements of the titlepages.
<!element title - o (%inline, subtitle?) +(newline)>
<title>
tag.
You don't need to close thatone.
A title may contain a subtitle started by the <subtitle>
tag.
If you look at the headerpage of this document you'll find it to be mapped from the tags:
<title>Linuxdoc Reference <subtitle>A introduction to the linuxdoc dtd
<!element author - o (name, thanks?, inst?, (and, name, thanks?, inst?)*)>
<author>
tag.
If you don't note the name
tag itīs imlicitly placed.
The author has also optional items wich can be tagged within the
author
tag.
If you want to say thanks to anyone (might be somebody providing usefull
information) you place it within the <thanks>
tag.
Next, if your writing is done in your position of an institution
staff member, place it within the <inst>
tag.
The <and>
tag is starting the whole story again,
as if there would be a second author
tag would have been started.
Clearly thisone is for coauthors.
If you want to mark your document with a date, you can do that with the
<date>
tag.
It's not checked weather you really place a valid date here, but don't abuse it.
This tag is intended for an abstract description of your document.
Don't mix the <abstract>
tag withh an indruduction wich is
likely to be placed inside the first section of your document
(see section
Sectioning).
<!element header - - (lhead, rhead) > <!element lhead - o (%inline)> <!element rhead - o (%inline)>
<header>
tag specifies what should be printed at the top of each
page.
It consists of a left heading i.e. <lhead>
and a right
heading i.e. <rhead>
).
Both elements are required, if a heading is used at all, but either may be
left empty, so that the effect of having only a left or right heading can be
achieved easily enough.
As we will see, an initial header can be given after the title page. Afterwards, a new header can be given for each new chapter or section. The header printed on a page is the one which is in effect at the end of the current page. So that the header will be that of the last section starting on the page.
If you place the <toc>
tag, a table of contense will be
generated, by looking the section heading, and adding references.
In a hyperref document, this might be hyperrefs, in a LaTeX document you will come to see the pagenumbers.Only the sections major to the
sect3
will be included.
If you place the <lof>
tag, a list of figures will be
generated, by looking the captions of the figures, and adding references.
If you place the <lot>
tag, a list of tables will be
generated, by looking the captions of the tables, and adding references.
Here you place various sections according section Sectioning. There is no body tag. The body starts with the first chapter, section or paragraph.
In the end of the article you can place the <appendix>
tag
Really you shouldn't think about people (e.g. m.d.s knifing your belly here., wich starts a area of appended sections. The
appendix
tag implies a different section numbering type to the
following section tags.
It's intended to gather all the <cites>
and <ncites>
you used within your document. The <biblio>
tag will be replaced
by a bibliography according the mapping type of the document,
maybe by hyperrefs maybe by section numbers or anything wich might be useful.
Until now I've not been able to create a .bbl
file, so I
wasn't able to verify.
A footnote may be place in any spot of your document.
Exactly the spot in yout document where you are placing
the <footnote>
tag should be the one where the reference to the
tagged text shuld be rendered.
It should be used for additional information, wich is not necessary for
understanding the primary purpouse of yor document
but might be usefull, interesting, or funny.
Whereas the last one is not always true, even if you try.anywhere within the article.
<!element report - - (titlepag, header?, toc?, lof?, lot?, p*, chapt*, (appendix, chapt+)?, biblio?) +(footnote)>
<report>
tag the
toplevel is grouped by the <chapt>
tag (see
Sectioning). The rest of the structure is identical to the
article class
Article Tag.
<!element book - - (titlepag, header?, toc?, lof?, lot?, p*, chapt*, (appendix, chapt+)?, biblio?) +(footnote) >
<book>
tag.
<!entity % addr "(address?, email?, phone?, fax?)" > <!element letter - - (from, %addr, to, %addr, cc?, subject?, sref?, rref?, rdate?, opening, p+, closing, encl?, ps?)>
Also the purpose of the letter document class should be quite self
explaining. Place a <letter>
tag if you want to write one.
The letter's tags ar described in table Tags in a letter
tag | mandatory | what's it |
from | yes | from sender |
address | no | sender's address |
no | sender's email | |
phone | no | sender's phone |
fax | no | sender's fax |
to | yes | receiver |
address | no | receiver's address |
no | receiver's email | |
phone | no | receiver's phone |
fax | no | receiver's fax |
cc | no | carbon copy |
subject | no | letters subject |
sref | no | sender's reference |
rref | no | receiver's reference |
rdate | no | received date?? |
opening | yes | opening |
paragraphs | yes | see Paragraphs |
closing | yes | closing |
encl | no | enclosure |
ps | no | post scriptum |
|
<!element telefax - - (from, %addr, to, address, email?, phone?, fax, cc?, subject?, opening, p+, closing, ps?)>
<telefax>
tag the receiver's <fax>
tag becomes mandatory.
Should be obvious why.
<!element slides - - (slide*) >
<slides>
tag is a
very simple one.
It contains single slide(s) startes by a <slide>
tag.
Nothing else.
If not explicitly written the first slide is started implicitly.
<!element slide - o (title?, p+) >
<slide>
tag is only allowed within the slides document class.
A slide may contain:
A title (see section The Title Tag) and one or more paragraphs (see section Paragraphs). That's all.
<!element notes - - (title?, p+) >
<notes>
tag only a
title (see section
The Title Tag)
and one or more paragraphs
(see section
Paragraphs) are allowed.
<!element manpage - - (sect1*) -(sect2 | f | %mathpar | figure | tabular | table | %xref | %thrm )>
man
programm.
In a document classified by a <manpage>
tag the topleve
section tag is the sect1
tag (see section
Sectioning), for easy pasting manual pages into an article
or book document class.
The exception here to the nortmal sectioning is, that there is only one
subsection level allowed (sect2
).
<!entity % inline " (#pcdata | f| x| %emph; |sq| %xref | %index | file )* " >
Parsed character data is just normal written text within the flow wich may contain other inlines.
Inline mathematical formulas according to the maths.dtd
. See
The Formula Tag.
The external tag wich is bypassing the parser. Tagged data walks directly into the mapped file. See chapter The External Tag for detailed information.
Emphasizes of the text. See chapter Emphasizes.
Shortquotes within the textflow. See chapter The Short Quote Tad.
XReferecnces within the text or external references. See chapter Labels and References.
Again I can't explain this one. If you can, please mail.
Again I can't explain this one (I only could guess about picture files in eps). If you can, please mail.
<!element chapt - o (%sect, sect*) +(footnote)> <!element sect - o (%sect, sect1*) +(footnote)> <!element sect1 - o (%sect, sect2*)> <!element sect2 - o (%sect, sect3*)> <!element sect3 - o (%sect, sect4*)> <!element sect4 - o (%sect)>
Also the chapt
tag is a sectioning
tag.
is done by the according elements, forming the section tree.
They are bringing the various paragraphs within our document to follow a
nice tree.
The top level tag and the allowed depth is varying with the document
class (see section
The Document Class).
The normal hierarchy is
chapt sect sect1 sect2 sect3 sect4
Just take a book, look the table of conetents and you will see.
Each of the tags out of the sectionings has nearly the same syntax.
All of them owe a heading.
The heading
tag is placed implicitly if you don't note it down.
Also the each of the sectioning tags may contain a header
tag, changing
the current document header (see section
The Header Tag).
Within the you may place subordinate sections and paragraphs (see Paragraphs).
Some of the sectioning tags may only appear in special document classes ( Document Classes).
It's wise to place a label tag after the text of the section tag, even if you don't want to refer to the section Labels and references. Later when your document grows you might want to.
<!entity % sectpar " %par; | figure | tabular | table | %mathpar; | %thrm; | %litprog; "> <!entity % par " %list; | comment | lq | quote | tscreen " > <!entity % litprog " code | verb " >
Each of the here described tags form a paragraph.
For obvious reason a paragraph is normally
The behaviour of the exceptionsstarting and ending with a new line.figure
andtabular
are explained there.
How else you would notice it's a paragraph ?
There are some tags, wich always form a paragraph, and one way to form a paragraph implicitly. There are various types of paragraphs, because not every type of paragraph is allowed to appear in every document class in every place.
The different types of paragraphs are explained in the next sections.
For more details about %litprog;
see
Literate Programming.
Normal paragraphs can be formed in two ways:
The <p>
tag is starting a new paragraph.
This tag is mandatory if you want to finish a section header without
explicitly closing the sect
tag.
In this case <p>
tag then closes the <sect>
tag
automatically.
A empty line between two paragraph is implicitly starting a new
paragraph.
Take care within descriptive
lists. There a empty <tag>
tag will not be paragraphed by an empty line.
<!entity % list " list | itemize | enum | descrip " >
<!element item o o ((%inline; | %sectpar;)*, p*) >
<!element list - - (item+)>
The list tag will be mapped to a nacked list without bullets, numers or anything else.
To see it, I place a small example:
<list> <item>A point <item>Another one <item>Last </list>
Will look (depending on the mapping) like:
<!element itemize - - (item+)>
The itemize tag will be mapped to a list with bullets, wich is usually place for lists where the order of the items is not important.
A small example:
<itemize> <item>A point <item>Another one <item>Last </itemize>
Will look (depending on the mapping) like:
<!element enum - - (item+)>
The enum tag will be mapped to a list with numbers.
A small example:
<enum> <item>A point <item>Another one <item>Last </enum>
Will look (depending on the mapping) like:
<!element descrip - - (tag?, p+)+ >
The descrip tag will be mapped to a descriptive list. The concept here is a little bit different than with the other types of lists mentioned above.
Here you place a tag (this time the tag's name is really litteraly
tag
) wich is described later on.
A small example:
<descrip> <tag/sgml/structured general markup language. <tag/html - hypertext markup language/ A sgml implementation. It contains some concepts about linking information together in a very convenient way. This made it to be so successful and to become the standard for documents published by the internet. <tag/internet/A worldwide connected internet (internet here as a technical term) </descrip>
Will look (depending on the mapping) like:
structured general markup language.
A sgml implementation. It contains some concepts about linking information together in a very covenient way. This made it to be so successfull and to become the standard for documents published by the internet.
A worldwide connected internet (internet here as a technical term)
The <figure>
and the <table>
tags form very special
paragraphs.
Not always they stay within the normal textflow.
Both of the tags can hold a loc
(loction) attribute wich is telling
how to handle the flow of this special paragraph.
The value of the loc
attribute is a string of up to four letters, where
each letter declares a location at which the figure or table may appear,
as described in table
Table Locations.
h | here | At the same location as in the SGML file |
t | top | At the top of a page |
b | bottom | At the bottom of a page |
p | page | On a separate page only with figures and tables
|
The default value of the loc attribute is top
.
<!element table - - (tabular, caption?) >
As you can see a table consists of the <table>
tag itself,
including a <tabular>
tag and a optional <caption>
tag.
The <tabular>
tag may also be placed without a <table>
tag so it is described in detail in it's own section
(see
Tabular Tag).
The caption is used also to place the entry for the list of tables if you stated one (see The List Of Tables Tag).
A short example will show how it's working together.
<table loc="ht"> <tabular ca="lcr"> Look|this|table@ Isn't|it|nice@ 1.234|mixed|columns </tabular> <caption>A sample table </table>
Look | this | table |
Isn't | it | nice |
1.234 | mixed | columns
|
The caption "A sample table" would be the name in the list of tables.
<!element figure - - ((eps | ph ), img*, caption?)>
<figure>
tag is equivalent to the
<table>
tag.
Instead of the <tabular>
tag you place either a <eps>
or a <ph>
tag.
<!attlist eps file cdata #required height cdata "5cm" angle cdata "0">
<eps>
tag is intended for including a external file in
encapsulated postscript™ format into the document.
The attributes of the <eps>
tag are:
The file
attribute needs the file name of a encapsulated
postscript™ file ending with a .ps
suffix.
The mandatory .ps
suffix must not be written.
The height of the space the file is zoomed to.
If you don't specify it defaults to 5cm.
Take care that there's no spcae between the number and the length unit
(i
, cm
).
The angle is given in normal degrees (0-360) and as the number is increasing the file is rotated counter clockwise.
A example:
<figure loc="here"> <eps file="logo" height="4cm" angle="15"> <img src="logo.gif"> <caption>A included encapsulated postscript™ </figure>
The img tag is ignored by LaTeX-mapping and useful for html, 'cause most browsers don't know about eps.
The caption here would go to the list of figures as decribed in section The List Of Figures Tag.
<!attlist ph vspace cdata #required>
vspace
attribte.
Caveat: The numerical argument for the vspace
attribte needs a
unit directly behind the number. Don't leave a space there
(same as for the height
attribute in
Encapsulated Postscript™ Tag.
<figure loc="ht"> <ph vspace="5cm"> <caption>A blank space. </figure>
Results to:
At this point you might want to look for your scissors and the glue.
<!element tabular - - (hline?, %tabrow, (rowsep, hline?, %tabrow)*, caption?) >
<tabular>
tag is interpreted as an own paragraph, if it is
written standalone.
Together with a <table>
tag it gets part of the paragraph of the
<table>
tag (see
Table tag).
Within the tabular
tag you have rows an collumns wich are separating the
text.
You have to have at least one collumn and one row.
Wouldn't be very usefull otherwise.
The <tabular>
tag has a mandatory ca
attribute for collumn
allignement.
The collumn allignement holds a single character for each collumn in their
order from left to right.
The chracters you may place per collumn described in table
Collumns allignements
char | alignment |
l | left |
c | centered |
r | right
|
In theory you should be able to place a | into the ca
attribure for
drawing a horizontal line for separating two collumns.
The problem: It doesn't work.
The parser accepts it nicely, only the LaTeX output will map |
to
{$|$}
wich is of course the set for four collumns with invalid collumn
allignement for all four collums.
I'll try to figure out what to do about it.
The columns within the <tabular>
tag are separated by a collumn
separator, the <colsep>
tag. The character |
is translated to
<colsep>
so you can also place that one instead
Less typing, more fun..
What's valid for collumns is also valid for rows. You separate the by a
row separator, the <rowsep>
tag.
The character @
is translated to <rowsep>
.
Optional you can place a horizontal line with the <hline>
tag.
Take care with that one:
The SGML tools will parse it nicely weather you place it in front of the row
you want under the line, or behind the end of the row you want over it.
But the only place to write it without causing the parser to shout
"error" is to write it dircetly and without space or newline behind
the row separator.
<tabular ca="lcr"> Look|this|table@<hline> Isn't|it|nice@ 1.234|mixed|columns@ </tabular>
Results in table Sample table for tabular tag
Look | this | table |
Isn't | it | nice |
1.234 | mixed | columns |
|
In LaTeX mapping everything works nice if you place a tabular tag without a table tag, only in the other mappings (e.g. html) it will be messed up.
<!entity % mathpar " dm | eq " >
A mathematical paragraph consits either of a displayed formula,
tagged by <dm>
No, sorry, not for Deutschmark! ;-)or an equation, tagged by
<eq>
.
They work very much the same.
Both of these tags contain a mathematical formula. See Mathematical Formulas for the tags valid here.
Because neither Netscape nor Microsoft has seen any need to add mathematical mappings to their browsers (like demanded and defined by w3c), there is no nice way of mapping, or at least displaying the math stuff in html. So if you view the online version, feel free to wonder what nonsense this man is telling here. Might be you should take a glance at the postscript version.
This tag displays a mathematical formula as a paragraph. The formula is mapped centered as a single line
No guarantee for that. You know: Mapping is a matter of taste..
<dm>(a+b)<sup/2/=a<sup/2/+2ab+b<sup/2/</dm>Is mapped to:
<dm>(a+b)<sup/2/=a<sup/2/+2ab+b<sup/2/</dm>Is mapped to:
<!entity % thrm " def | prop | lemma | coroll | proof | theorem " > <!element def - - (thtag?, p+) > <!element prop - - (thtag?, p+) > <!element lemma - - (thtag?, p+) > <!element coroll - - (thtag?, p+) > <!element proof - - (p+) > <!element theorem - - (thtag?, p+) >
thtag
.
For all the others the thtag
is giving the tag of the theorem
paragraph.
Yust try to use that one, wich is fitting the meaning of what you are typing.
<thrm> <thtag>Alexander's thrm</thtag> Let <f><fi/G/</f> be a set of non-trivially achievable subgoals and μ an order on <f><fi/G/</f>. μ is abstractly indicative if and only if it is a linearization of <f><lim><op>μ</op><ll><fi/G/</ll><ul>*</ul></lim></f>. </theorem>
The thrm
is replaced by the adequate tag.
Maybe somebody knowing about mathematics would be shocked about my abuse of the types, but I'm lazy so I simply copied the examples:
Definition ( Let def
):
*
Proposition ( Let prop
):
*
Lemma ( Let lemma
):
*
Corollation ( Let coroll
):
*
Let *
The proof is just the same without the thtag
:
Let *
Both tags from a paragraph and have very similar behavior. Inside this tags most special characters don't need their named form as in section Named Symbols. The exceptions are:
end of tag open
In difference to the normal paragraph mapping white-spaces and newlines will be mapped literally (as you write them in your source).
Also (with respect to manual layout) the font for mapping will be a non-proportional one.
See the difference between IIWW and
IIWW
.
Aggain, I'm neither a native speaker not I love mathematics a lot. So I just placed some nonsense, wich might cause headache and grey hair for people who want to use this document for learning to formulate mathematical or physical theories.
Feel free to send better examples.
<!element code - - rcdata>
Use the code tag, if you want to write sourcecode example within your text.
A code sample
<code>
#include <stdio.h> int main() { printf("Hello world"); return 1; }
<!element verb - - rcdata>
Use the verbatim tag for anything else than sourcecode (use Code Tag for this) which needs the good old whitespace padding, like terminal hardcopy, ASCII-Graphics etc.
A verb sample
<verb>
///////// | * * | | | | | <---> | \_____/</verb>
Here the abstract inlines are broken down until only true and usable tags will remain. Let's recall:
<!entity % inline " (#pcdata | f| x| %emph; |sq| %xref | %index | file )* " >
<!entity % emph " em|it|bf|sf|sl|tt|cparam " >
The emphasizes are gathering the tags for emphasizing inline text.
The different types of emphasizes are:
em
-> The Emphasize TagI hate to be redundant but I have to say:
The emphasize tag you place for emphasized text.
Normally it's mapped to italic letters.
So if you write <em/a emphasized text/
it will be mapped to
a emphasized text.
it
-> The Italic TagThe italic tag you place for a cursive mapping. If you write
<it/a italic text/
it will be mapped to a italic text.
bf
-> The Boldface TagThe boldface tag you place for a bold mapping. If you write
<bf/a bold text/
it will be mapped to a bold text.
sf
-> The Swissfont TagI know that Tom Gordon from GMD is telling that this is the
sans serif
tag.
My interpretation of the sf is swissfont wich for me is more easy
to remember.
This is mapping the inlined text to a font wich is out of the helvetica family.
So <sf/a swissfont text/
will be mapped to
sl
-> The Slanted TagI think I skip the explanation. <sl/a slanted text/
will be
mapped to a slanted text.
tt
-> The Terminaltype TagText tagged with terminaltype will be placed inline, just like all the
other text within a paragraph. It will not be included into source
output if you are workink as described in section
Literate Programming, even if it's
looking like typed code. <tt/a terminal typed text/
will be
mapped to a terminal typed text
.
Normally this one could be viewed the same level like one of the emphasize tags, but the definition of the linuxdoc dtd is placing it same level like the emphasizes, and so I do.
The shortquote
tag is a inline quotation, not forming an own paragraph.
The text <sq/a short quote/
is mapped to "a short quote".
The formula tag allows us to note down a mathematical formula within the
normal text, not appearing in an own line. So the text
<f>x=y<sup>2</sup></f>
will be displayed as
x=y2. See
Mathematical Fomulas for
the tags valid within the formula.
The external tag is passing the tagged data directly through the parser, without modifying it. E.g. to LaTeX.
They can appear with in the tags listed in table Places of Mathematical Formulas
tag | description | see |
f | inline formula | The Formula Tag |
dm | displayed formula | Mathematical Paragraph |
eq | equation |
Mathematical Paragraph
|
If you view this document mapped to html you will notice that html has no nice way of displaying mathematical formulas.
After a little hand parsing the contents of a mathematical tag looks like:
<!element xx - - (((fr|lim|ar|root) | (pr|in|sum) | (#pcdata|mc|(tu|phr)) | (rf|v|fi) | (unl|ovl|sup|inf))*)>
xx
stands for f
, dm
or eq
. All of them are the same.
Because neither Netscape nor Microsoft has seen any need to add mathematical mappings to their browsers (like demanded and defined by w3c), there is no nice way of mapping, or at least displaying the math stuff in html. So if you view the online version, feel free to wonder what nonsense this man is telling here. Might be you should take a glance at the postscript version.
<!element fr - - (nu,de) > <!element nu o o ((%fbutxt;)*) > <!element de o o ((%fbutxt;)*) >
So what we see from it is, that a fraction consits of a numerator and a denumerator tag, wich again each one can hold a mathematical formula.
I think an example will tell you more:
<dm><fr><nu/7/<de/13/</fr></dm>
results to:
In case we want to to place 1/2 instead of the numerator without cleaning it up, we'll type:
<dm><fr><nu><fr><nu/1/<de/2/</fr></nu><de/13/</fr></dm>
Which results to:
<!element pr - - (ll,ul,opd?) > <!element in - - (ll,ul,opd?) > <!element sum - - (ll,ul,opd?) >
Each of them has a lower limit (ll
tag),
a upper limit (ul
tag) and a optional operand,
where each of them again may consist of a formula.
The tags are same in syntax like shown in table
Tags with upper-, lower limit and operator.
<!element lim - - (op,ll,ul,opd?) > <!element op o o (%fcstxt;|rf|%fph;) -(tu) > <!element ll o o ((%fbutxt;)*) > <!element ul o o ((%fbutxt;)*) > <!element opd - o ((%fbutxt;)*) >
You can use that one for operators with upper and lower limits other than
products, sums or integrals. The for the other types defined operator is
destinied by the op
tag, wich can contain again a mathematical formula.
n
<!element ar - - (row, (arr, row)*) > <!attlist ar ca cdata #required > <!element arr - o empty > <!element arc - o empty > <!entity arr "<arr>" > <!entity arc "<arc>" >
ar
) is noted down equivalent to a tabular (see
section
The Tabular Tag).
The differences in handling are:
<hline>
tag.ca
attribute character |
is not allowd.colsep
tag but with the arc
tag
(array collumn).rowsep
tag but with the arr
tag
(array row).|
and @
are mapped to the adequate separator
tag, so you really can note a array same way as a tabular.
<dm><ar ca="clcr"> a+b+c | uv <arc> x-y | 27 @ a+b | u+v | z | 134 <arr> a | 3u+vw | xyz | 2,978 </ar></dm>
Is mapped to:
<!element root - - ((%fbutxt;)*) > <!attlist root n cdata "">
root
tag, wich contains a n
attribute, holding the value for the "n'th" root.
<dm><root n="3"/x+y/</dm>
is mapped to:
<!element fi - o (#pcdata) >
With the figure tag you can place mathematical figures. The tagged characters are directly mapped to a mathematical figure. Which character is mapped to which figure you'll find in Mathematical Figures.
<!element rf - o (#pcdata) >
I'm really not sure about rf
. What should it be?
No formula is allowed within that tag.
<dm><rf/Binom:/ (a+b)<sup/2/=a<sup/2/+2ab+b<sup/2/</dm>
is mapped to:
The remaining tags simply modify the tagged formula, without implying any other tag. The effect is shown in table Mathematical tags without included tags
<!entity % xref " label|ref|pageref|cite|url|htmlurl|ncite " >
As soon as itīs a little bit more sophisticated a document will need references to other places within the document.
<!element label - o empty> <!attlist label id cdata #required>
A example could look like:
<sect1>Welcome to the article<label id="intro"> <p>...
<!element ref - o empty> <!attlist ref id cdata #required name cdata "<@@refnam>">
With this tag you can refer to a place within your document labeled as in Label Tag.
The way the reference is mapped in you document again depends to the mapper. May result to a hyper-ref (HTML) or a section number (LaTeX).
<!element pageref - o empty> <!attlist pageref id cdata #required>
A example for a pageref:
<pageref id="intro">
In the HTML mapping there is no use for pageref, because there are no page numbers. In LaTeX mapping the tag is mapped to the pagenumber of the reffered label.
<!element url - o empty> <!attlist url url cdata #required name cdata "<@@urlnam>" >
A example for a url:
<url url="http://www.gnu.org" name="GNU Organization">
The mapping to html brings up a hyper-ref in your document. The reference is the value of the url attribute, the text standing in the Hyperref is the name attribute's value.
In LaTeX mapping this one results to the name followed by the url.
<!element htmlurl - o empty> <!attlist htmlurl url cdata #required name cdata "<@@urlnam>" >
<htmlurl url="http://www.gnu.org" name="GNU Organization">
The only difference between this tag and the Url Tag is in the LaTeX mapping.
The LaTeX mapping simply drops the url attribute and emphasizes the name.
In all other cases it's absolutely the same as the url tag.
<!element cite - o empty> <!attlist cite id cdata #required>
AFAIK this one needīs bibTeX to work nicely. So I'm terribly sorry, but I was not jet able to make use of it. For that reason for sure I'm the wrong one to explain about it.
<!element ncite - o empty> <!attlist ncite id cdata #required note cdata #required>
Same as Cite Tag.
<!entity % index "idx|cdx|nidx|ncdx" > <!element idx - - (#pcdata)> <!element cdx - - (#pcdata)> <!element nidx - - (#pcdata)> <!element ncdx - - (#pcdata)>
tag | my translation |
idx | index |
cdx | code index (terminaltype index) |
nidx | invisible index |
ncdx | invisible code index (terminaltype index) |
|
The index tags serve for making a index of your document. They are only useful if you want do do LaTeX mapping. They only differ very slightly as mentioned in table Index elements.
There are two ways to include indices into your document. Look at both and decide.
<article opts="makeidx">
.sgml2latex -m mydocument.sgml
.mydocument.idx
.mydocument.idx
with the makeindex
command like makeindex mydocument.idx
.mydocument.ind
.sgml2latex -o tex -m mydocument.sgml
.mydocument.tex
.mydocument.tex
with the editor of your choice.\end{document}
(should be somewhere
close to the end of the file) and insert the text
\printindex
bevor this line.latex mydocument.tex
.mydocument.dvi
wich aggain you might
process with dvips
to generate a postscript document.
I'm currently working on a patch to the sgmltools to automate the inclusion and generation of a index. To find out the current state see http://www.bnhof.de/~uwe/lnd/indexpatch/index.html.
<!entity % litprog " code | verb " >
Think of perlpod
.
, but to write a big
document and later to extract the code from it.
People who don't like to document their code will not appreciate.The principle is: All text within
verb
and code
tags, will be gathered into a
sourcefile.
That's it, because for now I don't remember the name of the tool doing thatone.
Norman Welsh
Matt Welsh and Greg Hankins and Eric S. Raymond
Matt Welsh, <mdw@cs.cornell.edu>
This is a slightly modified list taken from [SGML-Tools User's Guide 1.0 ($Revision: 1.1.1.1 $)]. If you miss some, don't hesitate to mail. A lot of the named characters shown in table Named Characters are same as in the html-dtd.
There is a small number of whatever you want to name it. The look like named characters, but will be printed not always, or not at all.
Thin space:
d D
->d D
Emphasized space:
d D
-> d D
Normal space: /d D/ -> d D
No break space:
A spaces at wich the line is not allowed to be broken. Two words separated by
a nbsp
will be treated by parser and mapper to be a single long one.
Suggest Hyphen:
If the mapper is up to break a word, with has the shy
tag inside, it will
probably do the wordbreak at the place of the shy
tag and place a
hyphen instead. If no wordbreak is necessary the shy
expands to
nothging at all.
| ― |
The special mappings for characters you might use for building up mathematical figures are shown in table Mathematical Figures.
This is the linuxdoc.dtd
used to parse this document. The revision log,
revision comments and a few redundant lines are taken out for saving paper
and screenspace.
<!-- This is a DTD, but will be read as -*- sgml -*- --> <!-- ================================================= --> <!-- $Id: lnd.sgml,v 1.1.1.1 2000/03/05 14:40:31 uwe Exp $ This is LINUXDOC96 DTD for SGML-Tools. This was LINUXDOC.DTD, a hacked version of QWERTZ.DTD v1.3 by Matt Welsh, Greg Hankins, Eric Raymond, Marc Baudoin and Tristan Debeaupuis; modified from QWERTZ.DTD by Tom Gordon. <!entity % emph " em|it|bf|sf|sl|tt|cparam " > <!entity % index "idx|cdx|nidx|ncdx" > <!-- url added by HG; htmlurl added by esr --> <!entity % xref " label|ref|pageref|cite|url|htmlurl|ncite " > <!entity % inline " (#pcdata | f| x| %emph; |sq| %xref | %index | file )* " > <!entity % list " list | itemize | enum | descrip " > <!entity % par " %list; | comment | lq | quote | tscreen " > <!entity % mathpar " dm | eq " > <!entity % thrm " def | prop | lemma | coroll | proof | theorem " > <!entity % litprog " code | verb " > <!entity % sectpar " %par; | figure | tabular | table | %mathpar; | %thrm; | %litprog; "> <!element linuxdoc o o (sect | chapt | article | report | book | letter | telefax | slides | notes | manpage ) > <!-- `general' entity replaced with ISO entities - kwm --> <!entity % isoent system "isoent"> %isoent; <!entity urlnam sdata "urlnam" > <!entity refnam sdata "refnam" > <!entity tex sdata "[tex ]" > <!entity latex sdata "[latex ]" > <!entity latexe sdata "[latexe]" > <!entity tm sdata "[trade ]" > <!entity dquot sdata "[quot ]" > <!entity ero sdata "[amp ]" > <!entity etago '</' > <!entity Ae 'Ä' > <!entity ae 'ä' > <!entity Oe 'Ö' > <!entity oe 'ö' > <!entity Ue 'Ü' > <!entity ue 'ü' > <!entity sz 'ß' > <!element p o o (( %inline | %sectpar )+) +(newline) > <!entity ptag '<p>' > <!entity psplit '</p><p>' > <!shortref pmap "&#RS;B" null "&#RS;B&#RE;" psplit "&#RS;&#RE;" psplit -- '"' qtag -- "[" lsqb "~" nbsp "_" lowbar "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar > <!usemap pmap p> <!element em - - (%inline)> <!element bf - - (%inline)> <!element it - - (%inline)> <!element sf - - (%inline)> <!element sl - - (%inline)> <!element tt - - (%inline)> <!element sq - - (%inline)> <!element cparam - - (%inline)> <!entity ftag '<f>' -- formula begin -- > <!entity qendtag '</sq>'> <!shortref sqmap "&#RS;B" null -- '"' qendtag -- "[" lsqb "~" nbsp "_" lowbar "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar > <!usemap sqmap sq > <!element lq - - (p*)> <!element quote - - ((%inline; | %sectpar;)*, p*)+ > <!element tscreen - - ((%inline; | %sectpar;)*, p*)+ > <!element itemize - - (item+)> <!element enum - - (item+)> <!element list - - (item+)> <!shortref desmap "&#RS;B" null "&#RS;B&#RE;" ptag "&#RS;&#RE;" ptag "~" nbsp "_" lowbar "#" num "%" percnt "^" circ "[" lsqb "]" rsqb "{" lcub "}" rcub "|" verbar > <!element descrip - - (tag?, p+)+ > <!usemap desmap descrip> <!element item o o ((%inline; | %sectpar;)*, p*) > <!element tag - o (%inline)> <!usemap desmap tag> <!usemap global (list,itemize,enum)> <!entity space " "> <!entity null ""> <!-- <!shortref bodymap "&#RS;B&#RE;" ptag "&#RS;&#RE;" ptag '"' qtag "[" lsqb "~" nbsp "_" lowbar "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar> --> <!element figure - - ((eps | ph ), img*, caption?)> <!attlist figure loc cdata "tbp" caption cdata "Caption"> <!-- eps attributes added by mb and td --> <!element eps - o empty > <!attlist eps file cdata #required height cdata "5cm" angle cdata "0"> <!element ph - o empty > <!attlist ph vspace cdata #required> <!element img - o empty> <!attlist img src cdata #required> <!element caption - o (%inline)> <!shortref oneline "B&#RE;" space "&#RS;&#RE;" null "&#RS;B&#RE;" null -- '"' qtag -- "[" ftag "~" nbsp "_" lowbar "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar> <!usemap oneline tag> <!usemap oneline caption> <!entity % tabrow "(%inline, (colsep, %inline)*)" > <!element tabular - - (hline?, %tabrow, (rowsep, hline?, %tabrow)*, caption?) > <!attlist tabular ca cdata #required> <!element rowsep - o empty> <!element colsep - o empty> <!element hline - o empty> <!entity rowsep "<rowsep>"> <!entity colsep "<colsep>"> <!shortref tabmap "&#RE;" null "&#RS;&#RE;" null "&#RS;B&#RE;" null "&#RS;B" null "B&#RE;" null "BB" space "@" rowsep "|" colsep "[" ftag -- '"' qtag -- "_" thinsp "~" nbsp "#" num "%" percnt "^" circ "{" lcub "}" rcub > <!usemap tabmap tabular> <!element table - - (tabular, caption?) > <!attlist table loc cdata "tbp"> <!element code - - rcdata> <!element verb - - rcdata> <!shortref ttmap -- also on one-line -- "B&#RE;" space "&#RS;&#RE;" null "&#RS;B&#RE;" null "&#RS;B" null '#' num '%' percnt '~' tilde '_' lowbar '^' circ '{' lcub '}' rcub '|' verbar > <!usemap ttmap tt> <!element mc - - cdata > <!entity % sppos "tu" > <!entity % fcs "%sppos;|phr" > <!entity % fcstxt "#pcdata|mc|%fcs;" > <!entity % fscs "rf|v|fi" > <!entity % limits "pr|in|sum" > <!entity % fbu "fr|lim|ar|root" > <!entity % fph "unl|ovl|sup|inf" > <!entity % fbutxt "(%fbu;) | (%limits;) | (%fcstxt;)|(%fscs;)|(%fph;)" > <!entity % fphtxt "p|#pcdata" > <!element f - - ((%fbutxt;)*) > <!entity fendtag '</f>' -- formula end -- > <!shortref fmap "&#RS;B" null "&#RS;B&#RE;" null "&#RS;&#RE;" null "_" thinsp "~" nbsp "]" rsqb "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar> <!usemap fmap f > <!element dm - - ((%fbutxt;)*)> <!element eq - - ((%fbutxt;)*)> <!shortref dmmap "&#RE;" space "_" thinsp "~" nbsp "]" rsqb "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar> <!usemap dmmap (dm,eq)> <!element fr - - (nu,de) > <!element nu o o ((%fbutxt;)*) > <!element de o o ((%fbutxt;)*) > <!element ll o o ((%fbutxt;)*) > <!element ul o o ((%fbutxt;)*) > <!element opd - o ((%fbutxt;)*) > <!element pr - - (ll,ul,opd?) > <!element in - - (ll,ul,opd?) > <!element sum - - (ll,ul,opd?) > <!element lim - - (op,ll,ul,opd?) > <!element op o o (%fcstxt;|rf|%fph;) -(tu) > <!element root - - ((%fbutxt;)*) > <!attlist root n cdata ""> <!element col o o ((%fbutxt;)*) > <!element row o o (col, (arc, col)*) > <!element ar - - (row, (arr, row)*) > <!attlist ar ca cdata #required > <!element arr - o empty > <!element arc - o empty > <!entity arr "<arr>" > <!entity arc "<arc>" > <!shortref arrmap "&#RE;" space "@" arr "|" arc "_" thinsp "~" nbsp "#" num "%" percnt "^" circ "{" lcub "}" rcub > <!usemap arrmap ar > <!element sup - - ((%fbutxt;)*) -(tu) > <!element inf - - ((%fbutxt;)*) -(tu) > <!element unl - - ((%fbutxt;)*) > <!element ovl - - ((%fbutxt;)*) > <!element rf - o (#pcdata) > <!element phr - o ((%fphtxt;)*) > <!element v - o ((%fcstxt;)*) -(tu|%limits;|%fbu;|%fph;) > <!element fi - o (#pcdata) > <!element tu - o empty > <!usemap global (rf,phr)> <!element def - - (thtag?, p+) > <!element prop - - (thtag?, p+) > <!element lemma - - (thtag?, p+) > <!element coroll - - (thtag?, p+) > <!element proof - - (p+) > <!element theorem - - (thtag?, p+) > <!element thtag - - (%inline)> <!usemap global (def,prop,lemma,coroll,proof,theorem)> <!usemap oneline thtag> <!entity qtag '<sq>' > <!shortref global "&#RS;B" null -- delete leading blanks -- -- '"' qtag -- "[" ftag "~" nbsp "_" lowbar "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar> <!usemap global linuxdoc> <!element label - o empty> <!attlist label id cdata #required> <!-- ref modified to have an optional name field HG --> <!element ref - o empty> <!attlist ref id cdata #required name cdata "&refnam"> <!-- url entity added to have direct url references HG --> <!element url - o empty> <!attlist url url cdata #required name cdata "&urlnam" > <!-- htmlurl entity added to have quieter url references esr --> <!element htmlurl - o empty> <!attlist htmlurl url cdata #required name cdata "&urlnam" > <!element pageref - o empty> <!attlist pageref id cdata #required> <!element comment - - (%inline)> <!element x - - ((#pcdata | mc)*) > <!usemap #empty x > <!-- Hacked by mdw to exclude abstract; abstract now part of titlepag --> <!element article - - (titlepag, header?, toc?, lof?, lot?, p*, sect*, (appendix, sect+)?, biblio?) +(footnote)> <!attlist article opts cdata "null"> <!-- Hacked by mdw to exclude abstract; abstract now part of titlepag --> <!element report - - (titlepag, header?, toc?, lof?, lot?, p*, chapt*, (appendix, chapt+)?, biblio?) +(footnote)> <!attlist report opts cdata "null"> <!element book - - (titlepag, header?, toc?, lof?, lot?, p*, chapt*, (appendix, chapt+)?, biblio?) +(footnote) > <!attlist book opts cdata "null"> <!-- Hacked by mdw, abstract now part of titlepag --> <!element titlepag o o (title, author, date?, abstract?)> <!element title - o (%inline, subtitle?) +(newline)> <!element subtitle - o (%inline)> <!usemap oneline titlepag> <!element author - o (name, thanks?, inst?, (and, name, thanks?, inst?)*)> <!element name o o (%inline) +(newline)> <!element and - o empty> <!element thanks - o (%inline)> <!element inst - o (%inline) +(newline)> <!element date - o (#pcdata) > <!usemap global thanks> <!element newline - o empty > <!entity nl "<newline>"> <!-- Hacked by mdw --> <!element abstract - o (%inline)> <!usemap oneline abstract> <!element toc - o empty> <!element lof - o empty> <!element lot - o empty> <!element header - - (lhead, rhead) > <!element lhead - o (%inline)> <!element rhead - o (%inline)> <!entity % sect "heading, header?, p* " > <!element heading o o (%inline)> <!element chapt - o (%sect, sect*) +(footnote)> <!element sect - o (%sect, sect1*) +(footnote)> <!element sect1 - o (%sect, sect2*)> <!element sect2 - o (%sect, sect3*)> <!element sect3 - o (%sect, sect4*)> <!element sect4 - o (%sect)> <!usemap oneline (chapt,sect,sect1,sect2,sect3,sect4)> <!element appendix - o empty > <!element footnote - - (%inline)> <!usemap global footnote> <!element cite - o empty> <!attlist cite id cdata #required> <!element ncite - o empty> <!attlist ncite id cdata #required note cdata #required> <!element file - - (#pcdata)> <!element idx - - (#pcdata)> <!element cdx - - (#pcdata)> <!element nidx - - (#pcdata)> <!element ncdx - - (#pcdata)> <!element biblio - o empty> <!attlist biblio style cdata "linuxdoc" files cdata ""> <!element slides - - (slide*) > <!attlist slides opts cdata "null"> <!element slide - o (title?, p+) > <!entity % addr "(address?, email?, phone?, fax?)" > <!element letter - - (from, %addr, to, %addr, cc?, subject?, sref?, rref?, rdate?, opening, p+, closing, encl?, ps?)> <!attlist letter opts cdata "null"> <!element from - o (#pcdata) > <!element to - o (#pcdata) > <!usemap oneline (from,to)> <!element address - o (#pcdata) +(newline) > <!element email - o (#pcdata) > <!element phone - o (#pcdata) > <!element fax - o (#pcdata) > <!element subject - o (%inline;) > <!element sref - o (#pcdata) > <!element rref - o (#pcdata) > <!element rdate - o (#pcdata) > <!element opening - o (%inline;) > <!usemap oneline opening> <!element closing - o (%inline;) > <!element cc - o (%inline;) +(newline) > <!element encl - o (%inline;) +(newline) > <!element ps - o (p+) > <!element telefax - - (from, %addr, to, address, email?, phone?, fax, cc?, subject?, opening, p+, closing, ps?)> <!attlist telefax opts cdata "null" length cdata "2"> <!element notes - - (title?, p+) > <!attlist notes opts cdata "null" > <!element manpage - - (sect1*) -(sect2 | f | %mathpar | figure | tabular | table | %xref | %thrm )> <!attlist manpage opts cdata "null" title cdata "" sectnum cdata "1" > <!shortref manpage "&#RS;B" null -- '"' qtag -- "[" ftag "~" nbsp "_" lowbar "#" num "%" percnt "^" circ "{" lcub "}" rcub "|" verbar> <!usemap manpage manpage >