@Section
    @Title { Changing the overall format }
    @Tag { tbl_setu }
@Begin
@PP
All of the options apart from the @Code format options can be changed
setup.files.tables @Index { setup files for tables }
in the @Code { tbl } setup file, in which case the new values become
the default values for every table in the document.  This section
explains how to do it.  Changing options in the setup file can save a
lot of time, but its more important purposes are to promote consistency
and to allow document-wide formatting changes to be carried out easily.
@PP
The first step is to obtain your own copy of the setup file, @Code { tbl },
from the Lout system include directory.  You can find out where that
is by typing
@ID @Code { lout -V }
This prints out various things about Lout.  Supposing that it says
that the Lout system include directory is @Code { "/usr/lout/include" }, for
example, you can copy the setup file into your current directory,
renaming it @Code { mytbl }, with the Unix command
@ID @Code "cp  /usr/lout/include/tbl  mytbl"
or its equivalent on your system.  You will also need to make
@Code { mytbl } writable.
@PP
The next step is to replace the @Code "@SysInclude { tbl }" line at the
start of your document with @Code { "@Include { mytbl }" }.  This causes
Lout to read your copy of the setup file, not the one in the system
include directory.  Since the two files are currently identical, this
has changed nothing so far, but now you can change the options within
@Code mytbl and the changes will affect your document.
@PP
Your copy of the setup file has some lines beginning with @Code "#"
that are ignored by Lout, and then it has @Code { "@SysInclude { tblf }" }.
This line tells Lout to read file @Code tblf which contains the definition
of the @Code tbl package, so it should not be changed.  After it comes
the @Code "@TblSetup" @Code "@Use" clause, which looks like this:
@ID @OneRow @Code @Verbatim {
@Use { @TblSetup
    # paint { nopaint }
    # font { }
    # break { }
}
}
Only a few of the options are shown here.  To change a setup file
option, delete the @Code "#" in front of it and change the value.  For
example, suppose you want all table entries two points smaller than the
surrounding text:
@ID @OneRow @Code @Verbatim {
@Use { @TblSetup
    # paint { nopaint }
    font { -2p }
    # break { }
}
}
This relative specification of font size is available anywhere, not
just in setup files (Section {@NumberOf fonts}).
@PP
Some setup file options contain values which use the @Code "@OrIfPlain"
symbol:
@ID @Code "marginvertical { 0.3f @OrIfPlain 1f }"
This means that the value of @Code marginvertical is to be @Code "0.3f"
usually, but @Code 1f in plain text documents.  Feel free to leave these
symbols there when you change a value, or delete them if you prefer.
@End @Section
