groff_hdtbl - Man Page

The hdtbl macros consist of four base and three optional macros, controlled by about twenty arguments. The syntax is simple and similar to the HTML table model and nearly as flexible: you can write sequences of tokens (macro calls with their arguments and content data), separated by blanks and beginning with a macro call, into the same line to get compact and cleanly arrranged input. An advantage of hdtbl is that the tables are constructed without calling a preprocessor; this means that groff(7)'s full macro capabilities are available. On the other hand, table processing with hdtbl is much slower than using the tbl(1) preprocessor. A further advantage is that the HTML-like syntax of hdtbl will be easily converted to HTML; this is not implemented yet.

In this and the next section, we present examples to help users understand the basic workflow of hdtbl. First of all, you must load the hdtbl.tmac file. As with nearly all other groff macro packages, there are two possibilities to do so: Either add the line

.mso hdtbl.tmac

to your roff file before using any macros of the hdtbl package, or add the option

-m hdtbl

to the command line of groff (before the document file which contains hdtbl macros). Then you can include on or more tables in your document, where each one must be started and ended with the .TBL and .ETB macros, respectively.

In this man page, we approximate the result of each example as terminal output to be as generic as possible since hdtbl currently only supports the ps and pdf output drivers.

The simplest well-formed table consists of just single calls to the four base table macros in the right order. Here we construct a table with only one cell.

.TBL
.TR
.TD
contents of the table cell
.ETB

A terminal representation is

+------------------------------------------------------+
| contents-of-the-table-cell                           |
+------------------------------------------------------+

Equivalent to the above is the following notation.

.TBL .TR .TD "contents of the table cell" .ETB

By default, the formatted table is inserted into the surrounding text at the place of its definition. If the vertical space isn't sufficient, it is placed at the top of the next page. Tables can also be stored for later insertion.

Using ‘row-number*column-number’ as the data for the table cells, a table with two rows and two columns can be written as

.TBL cols=2
.  TR .TD 1*1 .TD 1*2
.  TR .TD 2*1 .TD 2*2
.ETB

A terminal representation is

+--------------------------+---------------------------+
| 1*1                      | 1*2                       |
+--------------------------+---------------------------+
| 2*1                      | 2*2                       |
+--------------------------+---------------------------+

Here we see a difference from HTML tables: The number of columns must be explicitly specified using the ‘cols=m’ argument (or indirectly via the ‘width’ argument, see below).

The contents of a table cell is arbitrary; for example, it can be another table, without restriction to the nesting depth. A given table layout can be either constructed with suitably nested tables or with proper arguments to .TD and .TH, controlling column and row spanning. Note, however, that this table

.TBL
.  TR
.    TD
.      nop 1*1 1*2
.  TR
.    TD
.      TBL cols=2 border=
.        TR
.          TD
.            nop 2*1
.          TD
.            nop 2*2
.      ETB
.ETB

and this table

.TBL cols=2
.  TR
.    TD colspan=2
.      nop 1*1 1*2
.  TR
.    TD
.      nop 2*1
.    TD
.      nop 2*2
.ETB

are similar but not identical (the use of .nop is purely cosmetic to get proper indentation).

The first table looks like

+------------------------------------------------------+
| 1*1 1*2                                              |
+------------------------------------------------------+
|                                                      |
| 2*1                         2*2                      |
|                                                      |
+------------------------------------------------------+

and the second one like

+------------------------------------------------------+
| 1*1 1*2                                              |
+---------------------------+--------------------------+
| 2*1                       | 2*2                      |
+---------------------------+--------------------------+

Here is the latter table in a more compact form.

.TBL cols=2 .TR ".TD colspan=2" 1*1 1*2
.            TR .TD 2*1 .TD 2*2 .ETB

If a macro has one or more arguments (see below), and it is not starting a line, everything belonging to this macro including the macro itself must be enclosed in double quotes.

The order of macro calls and other tokens follows the HTML model. In the following list, valid predecessors and successors of all hdtbl macros are given, together with the possible arguments.

Macro arguments are separated by blanks. The order of arguments is arbitrary; they are of the form

or

with the only exception of the optional argument of the macro .ETB, which is the string ‘hold’. Another possible form is

However, this is limited to the case where the macro is the first one in the line and not already enclosed in double quotes.

Argument values specified below as c are colors predefined by groff or colors defined by the user with the .defcolor request. Argument values d are decimal numbers with or without decimal point. Argument values m are natural numbers. Argument values n are numerical values with the usual groff scaling indicators. Some of the arguments are specific to one or two macros, but most of them can be specified with .TBL, .TR, .TD, and .TH. These common arguments are explained in the next subsection.

Most of the argument default values can be changed by the user by setting corresponding default registers or strings, as listed below.

.TBL [args]

Begin a new table.

predecessor: .TD, .TH, .ETB, cell contents
successor: .CPTN, .TR
arguments:

border=[n]

Thickness of the surrounding box border. ‘border=’ (no value) means neither a surrounding box border nor any horizontal or vertical separator lines between the table rows and cells. ‘border=0’ suppresses the surrounding box border, but still allows separator lines between cells and rows.
Default: ‘border=.1n’ (register ‘t*b’).

bc=c

Border color.
Default: ‘bc=red4’ (string ‘t*bc’).

cols=m

Number of table columns. This argument is necessary if more than one column is in the table and no ‘width’ arguments are present.
Default: ‘cols=1’ (register ‘t*cols’).

cpd=n

Cell padding, i.e., the extra space between the cell space border and the cell contents.
Default: ‘cpd=.5n’ (register ‘t*cpd’).

csp=n

Cell spacing, i.e., the extra space between the table border or vertical or horizontal lines between cells and the cellspace.
Default: ‘csp=.5n’ (register ‘t*csp’).

"tal=l|c|r"

Horizontal alignment of the table, if it is smaller than the line width. ‘tal=l’: left alignment. ‘tal=c’: centered alignment. ‘tal=r’: right alignment.
Default: ‘tal=l’ (register ‘t*tal’).

width='w1 [w2 [...]]'

Widths of table cells. w1, w2, ... are either numbers of type n or natural numbers with the pseudo-scaling indicator ‘%’, with the meaning “percent of the actual line length (or column length for inner tables, respectively)”. If there are less width values than table columns, the last width value is used for the remaining cells. The argument

width='1.5i 10%'

for example indicates that the first column is 1.5 inches wide; the remaining columns take 1/10 of the column length each.
Default: The table width equals the outer line length or column length; the columns have equal widths.

height=n

Height of the table. If the table with its contents is lower than n, the last row is stretched to this value.

.CPTN [args]

Text of caption.

The (optionally numbered) table caption. .CPTN is optional.

predecessor: .TBL
successor: .TR
arguments:

"val=t|b"

Vertical alignment of the table caption. ‘val=t’: The caption is placed above the table. ‘val=b’: The caption is placed below the table.
Default: ‘val=t’ (string ‘t*cptn’).

.TR [args]

Begin a new table row.

predecessor: .TBL, .CPTN, .TD, .TH, .ETB, cell contents
successor: .TD, .TH
arguments:

height=n

The height of the row. If a cell in the row is higher than n, this value is ignored; otherwise the row height is stretched to n.

.TD [args [cell contents]]

Begin a table data cell.

.TH [args [cell contents]]

Begin a table header cell.

Arguments and cell contents can be mixed. The macro .TH is not really necessary and differs from .TD only in three default settings, similar to the <TH> and <TD> HTML tags: The contents of .TH is horizontally and vertically centered and typeset in boldface.

predecessor: .TR, .TD, .TH, .ETB, cell contents
successor: .TD, .TH, .TR, .ETB, cell contents
arguments:

colspan=m

The width of this cell is the sum of the widths of the m cells above and below this row.

rowspan=m

The height of this cell is the sum of the heights of the m cells left and right of this column.

Remark: Overlapping of column and row spanning, as in the following table fragment (the overlapping happens in the second cell in the second row), is invalid and causes incorrect results.

.TR .TD 1*1 ".TD 1*2 rowspan=2" .TD 1*3
.TR ".TD 2*1 colspan=2"         .TD 2*3

A working example for headers and cells with colspan is

.TBL cols=3
.  TR ".TH colspan=2" header1+2 .TH header3
.  TR .TD 1*1 .TD 1*2 .TD 1*3
.  TR .TD 2*1 ".TD colspan=2" 2*2+3
.ETB

This looks like

+------------------------------+---------------+
|          header1+2           |    header3    |
+--------------+---------------+---------------+
| 1*1          | 1*2           | 1*3           |
+--------------+---------------+---------------+
| 2*1          | 2*2+3                         |
+--------------+-------------------------------+

A working example with rowspan is

.TBL cols=3
.  TR
.  TD 1*1
.  TD rowspan=2 1+2*2
.  TD 1*3
.
.  TR
.  TD 2*1
.  TD 2*3
.ETB

which looks like

+--------------+---------------+---------------+
| 1*1          | 1+2*2         | 1*3           |
+--------------+               +---------------+
| 2*1          |               | 2*3           |
+--------------+---------------+---------------+

.ETB [hold]

End of the table.

This macro finishes a table. It causes one of the following actions.

• If the argument ‘hold’ is given, the table is held until it is freed by calling the macro .t*free, which in turn prints the table immediately, either at the current position or at the top of the next page if its height is larger than the remaining space on the page.
• Otherwise, if the table is higher than the remaining space on the page, it is printed at the top of the next page.
• If neither of the two above constraints hold, the table is printed immediately at the place of its definition.

predecessor: .TD, .TH, .ETB, cell contents
successor: .TBL, .TR, .TD, .TH, .ETB, cell contents
arguments:

"hold"

Prevent the table from being printed until it is freed by calling the macro .t*free. This argument is ignored for inner (nested) tables.

.t*free [n]

Free the next held table or n held tables. Call this utility macro to print tables which are held by using the ‘hold’ argument of the .ETB macro.

Before creating the first table, you should configure default values to minimize the markup needed in each table. The following example sets up defaults suitable for typical papers:

.ds t*bgc white\" background color
.ds t*fgc black\" foreground color
.ds t*bc black\"  border color
.nr t*cpd 0.1n\"  cell padding

The file /usr/share/doc/groff/examples/hdtbl/common.roff provides another example setup in the “minimal Page setup” section.

A table which does not fit on a partially filled page is printed automatically on the top of the next page if you append the little utility macro t*hm to the page header macro of your document's main macro package. For example, say

.am pg@top
.  t*hm
..

if you use the ms macro package.

The macro t*EM checks for held or kept tables, and for missing ETB macros (table not closed). You can call this macro by appending it the to end-of-input macro of the main, or “full-service”, macro package your document uses. For example, try

.am pg@end-text
.  t*EM
..

if you use the ms package.

Please send your comments to the groff mailing list or directly to the author.

The hdtbl macro package was written by Joachim Walsdorff.

groff(1)

provides an overview of GNU roff and details how to invoke groff at the command line.

groff(7)

summarizes the roff language and GNU extensions to it.

tbl(1)

describes the traditional roff preprocessor for tables.

groff(1), groff_tmac(5).