path: root/Master/texmf-dist/doc/generic/tap/tapdoc.tex

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\input tap
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\newif\ifpenetrating
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\penetratingtrue % OK, this part we include for some experienced users ;-)
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% ---
% verbatim macros, see DeK, pp. 344, 380--382, 351--352
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\def\setupverbatim {\tt \advance\baselineskip-\verbatimbaselinecorr
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% ---
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\def\section#1. #2. {\bigskip\noindent {\bf #1.\enspace#2.}\ }
% ========================================================================
\immediate
  \write16{========================================================================}%
\immediate
  \write16{****** This text is to be processed further by T. Rokicki's DVIPS ******}%
\immediate
  \write16{English hyphenation patterns by D. Wujastyk and G. Toal are recommended.}%
\immediate
  \write16{========================================================================}
% ========================================================================
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    \line{\vbox to8.5pt{}\the\headline}\ifnum\pageno>1\kern2pt\hrule\fi
  \vss}
  \nointerlineskip}
\headline{\rm \ifnum\pageno>1
   \ifodd\pageno\else \the\pageno\fi
   \hfil\rm TAP -- a set of \TeX\ macros for typesetting tables using \PS\hfil
   \ifodd\pageno \the\pageno\fi
 \else\hfil\fi
}
\footline{\hfil}


\topglue-8mm
\centerline{\bf TAP -- a set of \TeX\ macros}
\centerline{for typesetting tables using \PS}
{\advance\baselineskip-1pt
\medskip
\centerline{\srm Version 0.75 of Thursday, March 30th, 2000}
\medskip
\centerline{\srm Bogus\l{}aw Jackowski, Piotr Pianowski and Piotr Strzelczyk}
\centerline{\srm BOP s.c., ul. Piastowska 70, 80-363 Gda\'nsk, Poland}
\centerline{\stt e-mail: B.Jackowski@GUST.org.pl}
}

\bigskip \bigskip

The starting point of this package was a neat package by Michael~J.~Ferguson.
With his kind permission we rebuilt the package from scratch. Some notational
``bells and whistles'' have been added, and---perhaps more importantly---the
package has been enhanced by \PS-oriented features (painting cells with an
arbitrary colour, drawing diagonals in cells,~etc.).

TAP macros are designed to be convenient and efficient in, say, 80--90\% of
typical cases; on the other hand, special cases always require special
treatment.

\medskip

\section 1. Overview. The general form of the table is as follows:

\medskip \verb
\begintable
?table preamble?
?table row(s)?
\endtable
\brev \medskip

{\it Table preamble\/} will be described momentarily.

{\it Table row\/} can be either a {\it horizontal rule}, or a {\it normal
row}, or an {\it anchor row\/} (see the section on using \PS).

\smallskip

{\it Horizontal rules\/} can be obtained using two macros, ?\-? and ?\=?. A
normal (0.4pt) rule is denoted by ?\-?, a thicker one (1.2pt) is denoted by
?\=?. Both can appear either as a full table rule or as a cell rule (see
examples below).

\smallskip

{\it Normal table rows\/} have the following form:

\smallskip \verb
\B?suffix(es)? ?cell contents? ?cell separator? ?cell contents? ?cell separator? ... \E?suffix?
\brev \smallskip

{\it Cell contents\/} seems obvious, {\it cell separator\/} can be one of the
three characters: {\it vertical bar}~?|?, {\it exclamation mark\/}~?!?, and
{\it double quotes\/}~?"?. The first one denotes a normal vertical rule
(0.4pt), the second one---a thicker rule (1.2pt), the last one---no rule.
The spaces preceding and following {\it cell separators\/} are ignored.

\smallskip

The simplest suffixes for the ?\B? and ?\E? commands ({\it begin\/} and {\it
end\/} of a row) are just cell separators, with exactly the same meaning. The
command ?\B?, however, may have an optional second suffix. Namely, one of the
five characters can be used: ?0? (zero), ?-?, ?+?, ?_?, ?^?, or ?:?. They
convey information about an extra space to be added above and/or below the
current line:

{
\setbox0\hbox{Suffix ?0?\enspace}\advance\parindent\wd0

 \item{Suffix ?0?} says that no extra space is needed, that is, that the
natural height of the line is required.

 \item{Suffix ?-?} says that the cells of a given row are to be ``squashed''
as if they had zero height. In order to keep ``squashed'' text lines
aligned, a strut is added to each cell.

 \item{Suffix ?+?} says that a normal strut should precede the current row
(the strut is defined as a ?\vrule? of zero width, height $h$ plus 0.25ex,
and depth $d$ plus 0.25ex, where $h$ and $d$ are the height and depth of
?\hbox{(pl}? under the assumption that the current font on entering the table
is used).

 \item{Suffix ?_?} says that a special strut (the normal strut lengthened
downwards by 0.5ex) should precede the current row---to be used before
(above) a horizontal rule.

 \item{Suffix ?^?} says that another special strut (the normal strut
lengthened upwards by 0.5ex) should precede the current row---to be used
after (below) a horizontal rule;

 \item{Suffix ?:?} says that yet another special strut (the normal strut
lengthened both upwards and downwards by 0.5ex) should precede the current
row (it is to be used between horizontal rules);

 \item{Suffix ?=?} followed by a dimen specifies explicitly the height of a
given row, stored globally in variable ?\tablerowheight?. The contents of a
cell is vertically centered. Suffix~?=0mm? is almost equivalent to
suffix~?-?. The only difference is that the former puts no strut at the front
of a cell. (This option was introduced in version~0.74 as a result of a
stimulating discussion with Tadeush Sheibak.)

}

\medskip

At the first glance, the classification of suffixes may look somewhat
arbitrary.  After thinking a while, however, you should admit that all the
listed cases occur in almost each table, therefore it makes sense to provide
standard means for handling them. This notation is supposed to be memorable
as the character~?-?  can be remembered as ``flat,'' character~?^? as ``up,''
character~?_? as ``down,'' character~?:? as ``both up and down,''
and character~?=? obviously as ``equal~to.''

If you don't like this approach, you may ignore the optional suffixes and add
lines containing only the necessary rules above and below a given line.

If you like it, however, there is one more macro exploiting the same
notation, namely, ?\D? (``distender''). This macro can be followed by the
same list of special characters: ?0?, ?-?, ?+?, ?_?, ?^?, ?:? or ?=?. As a
result, a rule of the null width and the desired height and depth is typeset.
Since ?\D-? causes no squashing of any objects, ?\D-? and ?\D0?  yield, in
fact, the same results. Exceptionally, ?\D=? is equivalent to ?\D0?. This
means that ?\D=?, unlike ?\B=?, does not gobble the dimen that follows
(TAP warns about it).

\medskip

{\it Table preamble\/} has the following form:

\medskip \verb
\begintableformat
?cell descriptor? ?cell separator? ?cell descriptor? ?cell separator? ...
\endtableformat
\brev \medskip

In this case, {\it cell separator\/} is a {\it double quote\/} character~?"?,
{\it cell descriptor\/} can be ?\left?, ?\center? or ?\right? command
(?\left? and ?\right? restore their original meaning in math). The last {\it
cell descriptor\/} can be preceded by an {\it ampersand\/}~?&?, if the last
cell descriptor is to be used for all subsequent cells.


\medskip

Finally, there is an operator for joining a couple of cells together into one
cell. It is represented by an {\it at\/}~character~?@?. For example, writing
?@6? means that the contents should be spread over six cells and the
template of the last cell is to be used for the placement.

\bigskip

\noindent {\csc Examples.} The following data

\medskip \verb
\begintable
\begintableformat \right " &\center \endtableformat
\=
\B!^     | Polish     |         |         \E!
\B!- No. |            | Polish  | English \E! % flat row
\B!_     | diminutive |         |         \E!
\-
\B!^  1. | Ala        | Alicja  | Alice   \E!
\B!+  2. | Ania       | Anna    | Ann     \E!
\B":               @4 $\cdots$            \E"
\B!_ 10. | Zuzia      | Zuzanna | Susan   \E!
\=
\endtable
\brev \medskip

\noindent yield the following table:

\medskip \moveright\parindent
\begintable
\begintableformat \right " &\center \endtableformat

\=

\B!^     | Polish     |         |         \E!
\B!- No. |            | Polish  | English \E! % flat row
\B!_     | diminutive |         |         \E!

\-

\B!^  1. | Ala        | Alicja  | Alice   \E!
\B!+  2. | Ania       | Anna    | Ann     \E!
\B":               @4 $\cdots$            \E"
\B!_ 10. | Zuzia      | Zuzanna | Susan   \E!

\=
\endtable

\medskip

Assume now that the cell containing the text ``No.'' is to be replaced by an
empty space, that is, we wish to have a table with an incision at the upper
left corner:

\medskip \moveright\parindent
\begintable
\begintableformat \right " &\center \endtableformat
\B"      !               @3 \=            \E! % incised row (slice)
\B"^     ! Polish     |         |         \E! % incised row (slice)
\B"-     !            | Polish  | English \E! % incised flat row (slice)
\B"_     ! diminutive |         |         \E! % incised row (slice)
\B! \=   ! \-         | \-      | \-      \E!
\B!^  1. | Ala        | Alicja  | Alice   \E!
\B!+  2. | Ania       | Anna    | Ann     \E!
\B":               @4 $\cdots$            \E"
\B!_ 10. | Zuzia      | Zuzanna | Susan   \E!
\=
\endtable
\medskip

Thinking in terms of ``horizontal slices'' is crucial here: such an approach
is natural for the ASCII notation, and the ASCII notation is, in turn,
intrinsic for typesetting using \TeX. You will admit that the solution is
still simple and legible:

\medskip \verb
\begintable
\begintableformat \right " &\center \endtableformat
\B"      !               @3 \=            \E! % incised row (slice)
\B"^     ! Polish     |         |         \E! % incised row (slice)
\B"-     !            | Polish  | English \E! % incised flat row (slice)
\B"_     ! diminutive |         |         \E! % incised row (slice)
\B! \=   ! \-         | \-      | \-      \E!
\B!^  1. | Ala        | Alicja  | Alice   \E!
\B!+  2. | Ania       | Anna    | Ann     \E!
\B":               @4 $\cdots$            \E"
\B!_ 10. | Zuzia      | Zuzanna | Susan   \E!
\=
\endtable
\brev \medskip

\section 2. Useful macros. A couple of macros is provided for handling a bit
more complex cases.

We found it useful to have the following abbreviations: ?\>? standing for
?\rlap?, ?\<? standing for ?\llap?, ?\P?~standing for ?\phantom?,
?\V?~standing for ?\vphantom?, ?\K? standing for vertical spacing (kerning
between rows).

A tilde ?~? returns the space of the width of the digit zero of a current
font which is useful for aligning the columns of numbers.

A one-parameter macro ?\F? sets the current font for the rest of the table,
for example, ?\F\it? switches the font to italic for the subsequent rows
(note that the font is not set globally). It should be used between rows
(after~?\E?  and before~?\B?).

Macro ?\X? takes a series of lines (separated by double backslashes ?\\?,
surrounded obligatorily by curly braces) as its parameter and returns a box
containing lines which are aligned depending on a template for the current
column. In order to override the inherited alignment template inside ?\X?,
you can use one-parameter macros ?\C?, ?\L?, or ?\R? for centring, aligning
to left, or aligning to right, respectively. There is also macro ?\x?  that
works similarly, but the resulting box is flat (its height and depth are
equal to zero) and centred with respect to a baseline.  Usually, ?\X? and
?\x?  expand to ?\halign?. If you don't want to break all lines manually
?\halign?  is inconvenient. In such a case you should supply a desired width
of the resulting box between the command name and the opening curly brace.
For example, ?\X?~?30mm?~?{?~\inverb contents?~?}? will cause that the
contents will be set as a paragraph of width 30mm (inheriting centring, left
alignment or right alignment from the template for a given column).

A pair of macros ?\Y? and ?\y? is very similar to the pair ?\X? and ?\x?
except that ?\vtop? is used for the construction of the resulting box instead
of~?\vbox?. This means that ?\x? and ?\y? are, in fact, equivalent.

Finally, you can use macros ?\center?, ?\left? and ?\right? also in the table
text, not only in the preamble. Their purpose is to override locally the
template set in the preamble of a table. The first command they expand to is
?\omit?, therefore no \TeX\ command may appear between cell separators and
these macros.

\section 3. Configurability. The basic parameters of TAP macros can be
adjusted to meet particular needs.

The width of the rules is controlled by two dimen registers: ?\trth? (default
0.4pt, for normal rules) and ?\TRTH? (default 1.2pt, for thicker rules). The
macro ?\defaultstrut?  determines the height of rules inserted by the
macro~?\B? (see section ``Overview'') and can also be adjusted if needed.

Another quantity that you may wish to adjust is a cell margin. It is governed
by a dimen register ?\cellmarg?, set at the beginning of a table to a default
value 0.5em a current font.

In more complex cases, it may turn out that the actual parameterization does
not provide sufficient flexibility and introducing new macros or modifying
existing ones may turn out unavoidable. Fortunately, \TeX\ programs are
available mostly as sources. If programs are exceedingly large (\LaTeX\ may
serve as a notable example), modifying them is nearly impossible. We hope,
however, that here the task is not as difficult as it may appear at the first
glance. If you are bold enough, you will certainly be able to make the
alterations you need.

Before you go so far, however, try to adjust table settings by assigning a
befitting value to either ?\everytable? or ?\thistable?, both being token
registers, prior to setting a table. For example, if you want to override the
previously mentioned meaning of ?\<? and ?\>? in all subsequent tables, you
may use the statement ?\everytable{\def\<{$<$}\def\>{$>$}}?. The assignment
?\thistable{\def\<{$<$}\def\>{$>$}}? affects only the first ensuing table.

\section 4. Active characters. The ``magic'' characters ?|?, ?!?, ?"?, and
?@? are active inside a table (i.e., they are assigned category~13). You
should be aware that using active characters is a mixed blessing: on one
hand, notation becomes more legible, on the other hand, using active
characters foretells troubles, because they cannot be used in parameters to
most \TeX\ macros. For example, the construction ?\centerline? ?{\begintable?
?...?  ?\endtable}?  will not work since ?\centerline? swallows its parameter
before ?\begintable?  changes the category codes. Incidentally, the
construction ?\line?  ?{\hss\begintable?  ?...?  ?\endtable\hss}? does work.
Can you see why\?

In order to facilitate dealing with cases where a table---for some
reasons---is to be passed in a parameter, the macro ?\deftable? was
introduced. It allows to store the contents of a table or the fragment of a
table as a macro of a given name. For example, after saying ?\deftable\foo?
?\begintable? \inverb contents?  ?\endtable?  you may safely say
?\centerline? ?{\begintable?  ?\foo? ?\endtable}? (?\foo? is defined
globally).

\section 5. Forcing the width of a table. If a dimen register ?\desiredwidth?
is assigned a positive value (default is~0mm), a special technique is used in
order to obtain a table of the desired width by ``padding'' cells
appropriately with empty space. A self-suggesting approach, namely, using a
?\tabskip? glue, seems inadequate here because of the techniques used for
employing \PS\ (see below).

\section 6. Using \PS. Frequently, some cells or rows, or even the whole
table, is to be printed against a non-white background. Sometimes a diagonal
line is to be drawn across a cell. \PS\ is an excellent tool that can be used
for this purpose. The technique implemented in the TAP package bases on
?\special? commands we call ``anchors.'' Obviously, using ?\special? commands
is always driver-oriented. The current version of the TAP package is by
default meant for further processing using T.~Rokicki's DVIPS. Switching to
another DVI-to-\PS\ driver is trivial: it suffices to re-define the two
macros: ?\tapspecial? and ?\psunitsperinch?; the former defines the form of
the ?\special? (in DVIPS it is ?\special{ps:?~?...?~?}?), the latter---the
\PS\ macro that returns the resolution of a \PS\ document (in DVIPS it is
?Resolution?).

\TeX\ should be informed explicitly that anchors are to be employed. To do
this you should use a pair of macros ?\beginanchtable? ?...?  ?\endanchtable?
instead of ?\begintable? ?...? ?\endtable?.

A pair of macros, ?\uranchor? (cast an anchor at the {\it upper right\/}
corner of a cell) and ?\llanchor? (cast an anchor at the {\it lower left
corner\/} of a cell) can be put between rows for determining a rectangle to
be filled or crossed. The filling can be accomplished using macros
?\rectfill?  and ?\trianfill?, diagonal lines can be drawn using macro
?\diagstroke?. Macros ?\uranchor? and ?\llanchor? are supposed to be put
below and above a rule, respectively. Macros ?\rectfill?, ?\trianfill? and
?\diagstroke? can be put between any two rows of a table, their order,
however, is significant.

Here you have the exact syntax of the anchor commands:

\smallskip \verb
\uranchor ?number of a column? ?anchor identifier?
\brev \nobreak \verb
\llanchor ?number of a column? ?anchor identifier?
\rectfill {?cmyk coordinates of a colour?} ?anchor identifier?
\trianfill ?triangle descriptor? {?cmyk coordinates of a colour?} ?anchor identifier?
\brev \nobreak \verb
\diagstroke ?pen width? ?diagonal descriptor? {?cmyk coordinates of a colour?} ?anchor identifier?
\brev \medskip

\medskip

\noindent {\csc Remarks}.

\initabc

\itemabc {\it The number of a column\/} is simply a \TeX\ count (integer
number). If a whole row is meant rather than a particular cell you may use an
artificial column index~${\le0}$.

\itemabc {\it Anchor identifier\/} is an arbitrary sequence of characters
(typically a single letter).

\itemabc {\it Cmyk coordinates\/} are four numbers from the range
[0.\kern.15em.1] separated by spaces. Curly braces are obligatory, even
if you pass a macro expanding to cmyk coordinates as a parameter.

\itemabc {\it Triangle descriptor\/} can be one of the following two-letter
sequences:  ?SW?, ?SE?, ?NW?, ?NE? (standing for south-west, south-east,
north-west, and north-east, respectively). It determines the position of the
right angle of a triangle. The case of letters is meaningless, curly
braces should not be used.

\itemabc {\it Pen width\/} is just a \TeX\ dimen that is swallowed using
assignment, therefore curly braces should not be used.

\itemabc {\it Diagonal descriptor\/} can be one of the following sequences:
?BOTH?, ?DOWN?, ?UP?. The meaning, hopefully, is self-explaining. The case of
letters is meaningless, curly braces should not be used.

\bigskip

\noindent {\csc Examples}.

The following example shows how anchors can be used. The application is
admittedly artificial, nevertheless, it demonstrates possibilities.
The following \TeX\ code:

\medskip \verb
\beginanchtable
\brev \nobreak \verb
\begintableformat \right " &\center \endtableformat
\rectfill {0 0 0 .1} a          % fill a rectangle marked by the anchors suffixed `a'
\trianfill SE {0 0 0 .1} b      % fill a triangle marked by the anchors suffixed `b'
\diagstroke .4pt UP {0 0 0 1} b % draw a stroke marked by the anchors suffixed `b'
\=
\uranchor0a \uranchor1b
\B!^     | Polish     |         |         \E!
\B!-     |            | Polish  | English \E!
\B!_     | diminutive |         |         \E!
\llanchor2a \llanchor1b
\-
\B!^  1. | Ala        | Alicja  | Alice   \E!
\B!+  2. | Ania       | Anna    | Ann     \E!
\B":               @4 $\cdots$            \E"
\B!_ 10. | Zuzia      | Zuzanna | Susan   \E!
\=
\endanchtable
\brev \medskip

\smallskip

\noindent produces a table that is not so easy to obtain without \PS:

\smallskip

\medskip \moveright\parindent
\beginanchtable
\begintableformat \right " &\center \endtableformat

\rectfill {0 0 0 .1} a          % fill a rectangle marked by the anchors suffixed `a'
\trianfill SE {0 0 0 .1} b      % fill a triangle marked by the anchors suffixed `b'
\diagstroke .4pt UP {0 0 0 1} b % draw a stroke marked by the anchors suffixed `b'

\=
\uranchor0a \uranchor1b
\B!^     | Polish     |         |         \E!
\B!-     |            | Polish  | English \E!
\B!_     | diminutive |         |         \E!
\llanchor2a \llanchor1b
\-
\B!^  1. | Ala        | Alicja  | Alice   \E!
\B!+  2. | Ania       | Anna    | Ann     \E!
\B":               @4 $\cdots$            \E"
\B!_ 10. | Zuzia      | Zuzanna | Susan   \E!
\=

\endanchtable

\medskip

Finally, an excerpt from a real-life example demonstrating most of the
described features.

\newcount\anycount
\def\3{\afterassignment\threecont\anycount}
\def\threecont{\setbox0\hbox{\rm000}\hbox to\wd0{\hss\the\anycount}}
\def\4{\afterassignment\fourcont\anycount}
\def\fourcont{\setbox0\hbox{\rm0000}\hbox to\wd0{\hss\the\anycount}}

\medskip
\medskip
\thistable{\desiredwidth\hsize \longcalculationfalse}
\beginanchtable
\begintableformat
  \right " \left " &\center
\endtableformat
%
\rectfill{0 0 0 .1}a
\rectfill{0 0 0 .1}b
%
\=
\uranchor0a
\B!^        !           !        !   @3                      !  @2              \E!
\B!-        !           !        !   @3 citizens of Poland   !  @2 foreigners   \E!
\B!_        !           !        !   @3                      !  @2              \E!
\B!- \center{\X{group/\\subgroup}}
     !  \center{\X{name\\of the group}} !  \X{number\\of tested\\persons}
                                  !                          @5  \-             \E!
\B!^        !           !         !         |        |       !        |         \E!
\B!-        !           !         !\X{after leaving\\the country}
                                  |\X{not leaving\\the country}
                                  |\X{missing\\data}
                                  !\X{from Africa\\and Asia}
                                  |\X{from\\Cuba} \E!
\B!_        !           !         !         |        |        !        |        \E!
\llanchor0a
\=
\B!  @8 \vrule width 0mm height 0.75mm \E!
\=
\uranchor1b
\F\bf
\B!:  I.    ! disease X ! \4  378 ! \4  262 | \3  62 | \3   0 ! \3  51 | \3   3 \E!
\F\rm
\-
\B!^  1.    ! variant A ! \4  195 ! \4  131 | \3  38 | \3   0 ! \3  23 | \3   3 \E!
\B!+  2.    ! variant B ! \4  131 ! \4   95 | \3  24 | \3   0 ! \3  12 | \3   0 \E!
\B!_  3.    ! variant C ! \4   52 ! \4   36 | \3   0 | \3   0 ! \3  16 | \3   0 \E!
\=
\F\bf
\B!^        ! control   !         !         |        |        !        |        \E!
\K-.5pt % tiny correction of vertical spacing
\B!- II.    !           ! \4 3990 ! \4 2808 | \3 276 | \3 143 ! \3 577 | \3 186 \E!
\K-.5pt % tiny correction of vertical spacing
\B!_        ! group     !         !         |        |        !        |        \E!
\llanchor1b
\=
\endanchtable
\medskip
\medskip

As usually, real-life examples demonstrate not only the advantages of a
method, but also uncover its drawbacks. In this particular example, the main
difficulty was a convenient alignment to the right both bold and roman
numbers and centring the result in a column. If the only typeface used were
either roman or bold, macro tilde~?~?~might have been used (see section
``Useful macros'').  Aligning digits of varying width can be considered a
weird demand and the TAP package is not supposed to be prepared for such
cases.

\smallskip

We decided to define macros putting a number into a box of a desired width.
It sufficed to introduce two such macros, ?\3?  and ?\4?, for formatting
three and four digit numbers, respectively (note that they are not defined in
the TAP~package):

\medskip \verb
\newcount\anycount
\def\3{\afterassignment\threecont\anycount}
\def\threecont{\setbox0\hbox{\rm000}\hbox to\wd0{\hss\the\anycount}}
\def\4{\afterassignment\fourcont\anycount}
\def\fourcont{\setbox0\hbox{\rm0000}\hbox to\wd0{\hss\the\anycount}}
\brev \medskip \medskip

The \TeX\ code for the table reads:

\nobreak \medskip

\medskip\verb
\thistable{\desiredwidth\hsize}% set the width of this table to \hsize
\beginanchtable
\begintableformat
  \right " \left " &\center
\endtableformat
%
\rectfill{0 0 0 .1}a
\rectfill{0 0 0 .1}b
%
\=
\uranchor0a
\B!^        !           !        !   @3                      !  @2              \E!
\B!-        !           !        !   @3 citizens of Poland   !  @2 foreigners   \E!
\B!_        !           !        !   @3                      !  @2              \E!
\B!- \center{\X{group/\\subgroup}}
     !  \center{\X{name\\of the group}} !  \X{number\\of tested\\persons}
                                  !                    @5  \-                   \E!
\B!^        !           !         !         |        |       !        |         \E!
\B!-        !           !         !\X{after leaving\\the country}
                                  |\X{not leaving\\the country}
                                  |\X{missing\\data}
                                  !\X{from Africa\\and Asia}
                                  |\X{from\\Cuba} \E!
\B!_        !           !         !         |        |        !        |        \E!
\llanchor0a
\=
\B!  @8 \vrule width 0mm height 0.75mm \E!
\=
\uranchor1b
\F\bf
\B!:  I.    ! disease X ! \4  378 ! \4  262 | \3  62 | \3   0 ! \3  51 | \3   3 \E!
\F\rm
\-
\B!^  1.    ! variant A ! \4  195 ! \4  131 | \3  38 | \3   0 ! \3  23 | \3   3 \E!
\B!+  2.    ! variant B ! \4  131 ! \4   95 | \3  24 | \3   0 ! \3  12 | \3   0 \E!
\B!_  3.    ! variant C ! \4   52 ! \4   36 | \3   0 | \3   0 ! \3  16 | \3   0 \E!
\=
\F\bf
\B!^        ! control   !         !         |        |        !        |        \E!
\K-.5pt % tiny correction of vertical spacing
\B!- II.    !           ! \4 3990 ! \4 2808 | \3 276 | \3 143 ! \3 577 | \3 186 \E!
\K-.5pt % tiny correction of vertical spacing
\B!_        ! group     !         !         |        |        !        |        \E!
\llanchor1b
\=
\endanchtable
\brev

\section 7. Implicit anchors ({ver. 0.74}). Under pressure from TAP users, a
few new drawing capabilities has been introduced. The most important are
pairs of commands that simplify using anchors: ?\bstroke?~?...?~?\estroke?
and ?\brectangle?~?...?~?\erectangle?. You don't need to specify anchors
explicitly when using them. Below, the syntax of these commands is
specified:

\smallskip \verb
\brectangle ?corner descriptor? ?number of a column? ?anchor identifier?
\brev \nobreak \verb
\erectangle ?cmyk colour? ?corner descriptor? ?number of a column? ?anchor identifier?
\bstroke ?corner descriptor? ?number of a column? ?anchor identifier?
\brev \nobreak \verb
\estroke ?pen width? ?cmyk colour? ?dashing pattern? ?corner descriptor?
\brev \nobreak \verb
  ?number of a column? ?anchor identifier?
\brev

\noindent {\csc Remarks}. Nearly all notions occurring in the syntax
definition were already mentioned in the description of anchor commands.
Only {\it dashing pattern\/} and {\it corner position\/} needs some
explanations:

\initabc

\itemabc {\it Corner descriptor\/} is a two-letter sequence; currently, the
following descriptors are admissible: {\it ur}, {\it ul}, {\it lr}, {\it ll},
{\it nr}, and {\it nl}.  They stand for: {\it upper-right}, {\it upper-left},
{\it lower-right}, {\it lower-left}, {\it no-offset-right}, {\it
no-offset-left}, respectively.  A bit misleading is perhaps the notion of
{\it upper\/} and {\it lower} positioning. Their meaning is related to the
thickness of the rule. It is assumed that anchors positioned with {\it ur},
{\it ul\/} are placed {\it below a horizontal rule}, and hence at {\it the
top of a cell\/}; the corner descriptor helps TAP macros to compute extra
offset in order to ``hide'' anchors under rules (?\anchoffset?). Similarly,
descriptors {\it lr}, {\it ll\/} concern anchors that are positioned {\it
above a rule}, and hence at {\it the bottom of a cell}. Descriptors {\it nr},
{\it nl\/} simply ignore extra offsets. (See also Section~8 below.)

Needless to say, macros ?\uranchor? and ?\llanchor? use, actually,
the descriptors {\it ur}~and~{\it ll}.

\itemabc {\it Dashing pattern\/} is a sequence of real numbers that defines
the length (in \TeX\ points) of dashed fragments and gaps between them. The
form is similar to that of the pattern argument of the \PS\ command
?setdash?. In particular, empty pattern means solid line. The example below,
again admittedly artificial, demonstrates the variety of cases that can be
defined using the operations ?\bstroke?~?...?~?\estroke? and
?\brectangle?~?...?~?\erectangle?:

\setbox0\vbox{\verb
\beginanchtable \begintableformat &\center \endtableformat
\=
\brectangle nl 1 {ala}
\bstroke nl 3 {kot1}
\bstroke nr 3 {kot2}
\B!: Ala     "    ma   "   kota   \E!
\estroke \TRTH {0 1 0 0} {3} nr 3 {kot1}
\ontext\estroke \TRTH {0 1 0 0} {3 3} nl 3 {kot2}
\erectangle {0 0 1 0} nr 2 {ala}
\bstroke nl 0 a
\ontext\estroke 1pt {1 1 0 0} {1 1 3 1} nr 0 a
\brectangle nl 2 a
\B!: Ola     "        @2 psa      \E!
\erectangle {0 0 .7 0} nr 0 a
\=
\endanchtable
\brev}

\setbox1\vbox{
\beginanchtable
\begintableformat &\center \endtableformat
\=
\brectangle nl 1 {ala}
\bstroke nl 3 {kot1}
\bstroke nr 3 {kot2}
\B!: Ala     "    ma   "   kota   \E!
\estroke \TRTH {0 1 0 0} {3} nr 3 {kot1}
\ontext\estroke \TRTH {0 1 0 0} {3 3} nl 3 {kot2}
\erectangle {0 0 1 0} nr 2 {ala}
\bstroke nl 0 a
\ontext\estroke 1pt {1 1 0 0} {1 2 3 2} nr 0 a
\brectangle nl 2 a
\B!: Ola     "        @2 psa      \E!
\erectangle {0 0 .7 0} nr 0 a
\=
\endanchtable
}

\medskip

\line{\valign{\vss#\vss\cr
  \rlap{\copy0}\cr
  \noalign{\hfill}
  \copy1\cr
  \noalign{\kern15mm}
}}

\medskip

Observe the presence of the operator ?\ontext?, that hasn't yet been
mentioned. It can be used before either ?\estroke? or ?\erectangle? in order
to put a line or a rectangle on the top of table contents.

\section 8. More about anchors. The placement of anchors is a fairly complex
task. The main problem is that the position of the ``ceiling'' of a cell is
not available within \TeX{} program---the anchors can be placed only at the
``floor'' of a cell. Actually, anchor commands (like table rules) are invoked
in two ways:  either in a ?\noalign? clause (?\llanchor?  and ?\uranchor?
followed by an artificial column number equal to zero) or from inside a cell.
In the latter case, a dummy row of null height is created, containing an
appropriately placed anchor. In the figure presented below, white rectangles
symbolize cells, gray ones---rules; a white dot show a place where an anchor
command is invoked, a black dot---a place where finally a ?\special? command
containing a \PS{} code is placed; thick lines visualize distances ``known''
to anchor commands. The letters show various cases of the placement of
anchors:

{
\advance\parindent1.75\parindent
\def\node#1 {\item{\hbox to.8em{\hss$#1$\hss}---\kern-.5em}}

\node{A}   the placement of an anchor with the {\it ur\/} descriptor
           at the second column (e.g., ?\uranchor?~?2?~?...?);
\node{A'}  the example of an anchor with the {\it ur\/} descriptor,
           placed mistakenly above a rule, i.e., below a cell
           (e.g., ?\uranchor?~?2?~?...?);
\node{B}   the placement of an anchor with the {\it ll\/} descriptor
           at the second column (e.g., ?\llanchor?~?2?~?...?);
\node{B'}  the example of an anchor with the {\it ll\/} descriptor,
           placed mistakenly below a rule, i.e., above a cell
           (e.g., ?\llanchor?~?2?~?...?);
\node{C}   the placement of an anchor with the {\it ur\/} descriptor
           at ``column 0'', i.e., at the right edge of
           a table (e.g., ?\uranchor?~?0?~?...?); anchor casting
           takes place in a ?\noalign? clause and makes use of
           the current table width;
\node{D}   the placement of an anchor with the {\it ll\/} descriptor
           at ``column 0'', i.e., at the left edge of
           a table (e.g., ?\llanchor?~?0?~?...?); anchor casting
           takes place in a ?\noalign? clause;
\node{E}   the placement of an anchor with the {\it nl\/} descriptor
           at column~1;
\node{F}   the placement of an anchor with the {\it nr\/} descriptor
           at column~1.

}

\medskip

\centerline{\eps{tapanch.100}}

\section 9. Final remarks. As always, the ultimate documentation are the
source files, in this case ?tap.tex? and ?tapdoc.tex?. A~careful inspection
of the files may provide some hints, reveal possibilities not mentioned in
this documentation, explain some points that were explained vaguely.  The
code is not as simple as one would expect, however, it should be remembered
that there is a trade-off between notation and implementation. Here we
sacrificed the simplicity of implementation in favour of the ease of~use and
the legibility of user's \TeX~code.

\section 10. Acknowledgements. The authors express their gratitude to all
people who pointed out several deficiences of the TAP package and helped
to improve it with the penetrating comments.

\ifpenetrating

\bigskip

\section $\infty$. Fine points of using TAP.

\nobreak

\initabc

\smallskip

\itemabc The vertical rules (set by ?|? and ?!?) occupy, actually,
a separate column. The ?\cellmarg? setting does not affect these colomns.

\smallskip

\itemabc $\rm\hbox{?\parindent?}=0\,mm$ inside ?\X?, ?\x?, ?\Y?, and ?\y?
 if the width is specified explicitly (that is, in a ``paragraph'' mode).

\smallskip

\itemabc ?~?, ?\-?, ?\=? restore the meaning they have on entry to the table
in ?\X?, ?\x?, ?\Y?, and ?\y?, provided the width of a box is given
explicitly. Moreover, in math mode also ?\>? and ?\!? restore the meaning
they have on entry to the table (in plain they are defined as follows:
?\def\>{\mskip\medmuskip}? ?\def\!{\mskip-\thinmuskip}?). An exclamation mark
?!? and an at sign ?@? are directly available in math mode and inside ?\X?,
?\x?, ?\Y?, and~?\y?. The original meaning of ?\L? and ?\l? (presumably
Polish `L' and `l' \`a la Knuth) is assigned on the entry to a table to
?\Lslash? and ?\lslash?, respectively.

\smallskip

\itemabc Cell correction used for forcing a desired width is by default
symmetric; however, it can be forced to be asymmetric which is useful when
one wants to keep stiff cell margins. The cell correction is governed by
macros ?\symcellcorr? and ?\asymcellcorr?. If a cell correction becomes
dangerously small (less than ?\TRTH?), a warning is issued. Observe that
changing ?\asymcellcorr? to ?\symcellcorr? may cause that the warning
disappears (but not vice versa), or that the displayed correction is
different.

\smallskip

\itemabc In fact, there are three kinds of struts: a normal row strut, an
extended row strut and an inner strut (the latter to be used inside ?\X?,
?\x?, ?\Y?, and ?\y?). You can change the row strut using either of two
macros: ?\settablestrut? or ?\adjusttablestrut?. Both expect four dimens to
follow (not parameters): normal height, normal depth, extended height and
extended depth. A pair of macros ?\setstrut? and ?\adjuststrut? can be used
to specify the inner strut. Both macros expect two dimens to follow. It can
easily be guessed that ?\set...? macros assign a value while ?\adjust...?
macros increment the respective dimens by a specified value. By default,
inner and normal struts are identical.

\smallskip

\itemabc Prior to squashing the contents of a cell, an inner strut is put
in front of the contents. This guarantees that squashed cells containing
single lines will be vertically aligned. Can you predict, however, the result
of a construction like this: ?\B!-?~?Ala?~?!?~?\x{Ala}?~?\E!?, that is, what
is the consequence of a ``double squashing'': one ``global'' (suffix~?-?) and
one local (macro~?\x?)\?

\smallskip

\itemabc Horizontal rules are not squashed. \TeX\ has no means to produce
rules that expand to implicit dimensions and have a null thickness. As a
result, gaps may appear:

\def\castcirc{%
  \hfill
  \castat {\anchoffset} {\anchoffset}
    {\vbox to0mm{\vss\hbox to0mm{\hss\epsffile{circ.eps}\hss}\vss}}%
  \kern -\cellmarg
  \kern -\ifignorecellstate 1\else\ifcase\cellstate 2\or 1\or 0\fi\fi\cellcorr
}

\setbox0\vbox{
\verb
\begintable
\begintableformat &\center \endtableformat
\B"                !     @2  \=       \E!
\B":               !     @2 Name      \E!
\B"                !     @2  \-       \E!
\B"^               ! Alicja  |  Ala   \E!
\B"_               ! Zuzanna | Zuzia  \E!
\B!  \=            !     @2  \-       \E!
\B!: Altogether    |    2    |    2   \E!
\=
\endtable
\brev
}

\setbox1\hbox{\begintable
\begintableformat &\center \endtableformat
\B"                !     @2  \=       \E!
\B":               !     @2 Name      \E!
\B"                !     @2  \-       \E!
\B"^               ! Alicja  |  Ala   \E!
\B"_               ! Zuzanna | Zuzia  \E!
\B!  \=            !     @2  \-       \E!
\B"                "\castcirc"        \E"
\B!: Altogether    |    2    |    2   \E!
\=
\endtable}

\medskip
\line{\valign{\vss#\vss\cr
  \rlap{\copy0}\cr
  \noalign{\hfill}
  \copy1\cr
  \noalign{\kern5mm}
  \vbox to\ht0{\vss\epsffile{circmag.eps}\vss}\cr
}}
\medskip

\item{} A remedy is to add a kern correction immediately above the offending
line ?\B!?~?\=?~?!?~?@2?~?\-?~?\E!?, for example, ?\K-\TRTH?~?\K.5\trth?
(recall that ?\trth? and ?\TRTH? are the \TeX\ dimens that control the
thickness of table rules). Another possibility, perhaps more natural, is to
specify all vertical rules explicitly: ?\B!?~?\=?~?!?~?\-?~?|?~?\-?~?\E!?.

\smallskip

\itemabc In general, boxes can be squashed vertically either by setting a
box register using ?\vcenter? command and next setting the height and depth
of the box to 0$\,$mm, or by using ?\vbox{\vss?~?...?~?\vss}? construction.
In the former case, the box is centered with respect to the math axis of a
given font, in the latter case---with respect to the baseline. We consider
the latter approach more adequate for tables.

\smallskip

\itemabc The resulting width of a table is stored in a globally defined
macro ?\tablewidth?. If ${?\desiredwidth?>0}$, the value of ?\tablewidth? may
differ from the value of ?\desiredwidth? at the level of the actual accuracy
(governed by the dimen ?\widthaccuracy?).

\smallskip

\itemabc In ?\deftable? macro, ?\begintable? and ?\endtable? are just
separators, thus you may define a table ``in parts'' and then
combine some parts together:

\nobreak

\medskip \verb
\deftable\headA
\begintable
\begintableformat &\center \endtableformat
\endtable
\brev

\medskip \verb
\deftable\headB
\begintable
\begintableformat &\left \endtableformat
\endtable
\brev

\medskip \verb
\deftable\contents
\begintable
\B" table \E"
\B" contents \E"
\endtable
\brev

\medskip \verb
\centerline{\begintable\headA\contents\endtable} % centered table
\centerline{\begintable\headB\contents\endtable} % left-aligned table
\brev

\medskip

\itemabc In special cases you may also wish to use the table active
characters---there is a macro ?\tableactive? which makes the respective
characters active. There is no a ``reverse'' macro to ?\tableactive?
(similarly to macros ?\obeylines?  and ?\obeyspaces?). If it is to be used
locally, it should be used in a group.

\itemabc The width of a table is forced using a binary search method which
usually takes time. You may try a simpler method, much faster but not too
much reliable. The command controlling the choice of the method is
?\??iflongcalculation?. % ?\iflongcalculation? does not work;
                        % can you guess when and why?
 By default, ?\longcalculationtrue? is performed for every table, that is,
?\everytable{\longcalculationfalse}? or ?\thistable{\longcalculationfalse}?
can be used to override the default. If the process of forcing the width
fails, you will get a warning, and the best cure is to abandon the short-cut
method for that particular table.  (Note that the second ``anchor'' table is,
in fact, typeset using the short-cut method.)

\itemabc Both ?\begintable? and ?\beginanchtable? are defined with the
attribute ?\long?, however, inside a table the meaning of ?\par? is changed
to ?\empty?. This allows to use empty lines as separators of rows which
may help to improve the legibility of the table code. The original meaning of
?\par? is restored at the beginning of every ?\vbox?.

\itemabc The table rules need not to be black and the table background
needs not to be white. The colour of rules can be set by macro
?\tablerulecmyk?, the background colour---by ?\tablebkgcmyk?. The following
example shows how to use them:

\setbox0\vbox{\verb
\thistable{\tablerulecmyk{1 0 1 0}\tablebkgcmyk{0 0 1 0}}
\beginanchtable
\begintableformat &\center \endtableformat
\=
\B!:   Ala  | Alice  \E!
\-
\B!:  Zuzia | Susan  \E!
\=
\endanchtable
\brev}

\setbox1\vbox{
\thistable{\tablerulecmyk{0 1 1 0}\tablebkgcmyk{0 0 1 0}}
\moveright\parindent \beginanchtable
\begintableformat &\center \endtableformat
\=
\B!:   Ala  | Alice  \E!
\-
\B!:  Zuzia | Susan  \E!
\=
\endanchtable
}

\medskip
\line{\valign{\vss#\vss\cr
  \rlap{\copy0}\cr
  \noalign{\hfill}
  \copy1\cr
  \noalign{\kern20mm}
}}
\medskip

\item{} Note that the background colour can be used only with anchor tables,
as anchors are needed for putting the background patch. Moreover, you can say
?\tablerulecmyk{}? or ?\tablebkgcmyk{}?; in such a case the colour will be
ignored. As the matter of fact, TAP defaults are ?\tablerulecmyk{}?  and
?\tablebkgcmyk{0?~?0?~?0?~?0}?.

\itemabc Besides macros ?\bstroke?~?...?~?\estroke? and
?\brectangle?~?...?~?\erectangle? there are also ``advanced'' variants of
these macros: ?\bgenstroke?~?...?~?\egenstroke? and
?\bgenrectangle?~?...?~?\egenrectangle?. As their names suggest, they are a
bit more general and allow for using nearly arbitrary \PS\ code prior to
drawing a stroke or a rectangle, respectively. Their syntax is more
uniform than their ``user-friendly'' counterparts:

{\catcode`\@13 \let@\PS

\smallskip \verb
\bgenrectangle ?corner descriptor? ?number of a column? ?anchor identifier?
\brev \nobreak \verb
\egenrectangle ?@ code? ?corner descriptor? ?number of a column? ?anchor identifier?
\bgenstroke ?corner descriptor? ?number of a column? ?anchor identifier?
\brev \nobreak \verb
\egenstroke ?@ code? ?corner descriptor? ?number of a column? ?anchor identifier?
\brev

}

\fi

\end