[svdac~X] - Set "decimal alignment" character to X. This redefines the character that will be used by the tab commands when decimal alignment is requested. The default "decimal point" is the character common for American usage, i.e., [svdac~.] for both print and braille files (which produces dots 4-6 in the latter).
In Europe, and many other countries, a comma is used as the decimal point instead of a full stop or period. For example, "1,345.95" is written "1.345,95". Hence, one sets [svdac~,] to line up columns of figures using the comma instead of the period.
The principals here are virtually identical to those covered in Decimal Tabs, but DBT allows nearly any character to be defined as the character for "decimal" alignment, and this flexibility can be used to create a particular formatting effect.
For example, let us suppose we need to produce a list of e-mail addresses and we need them aligned on the @ sign.
Using [svdac~@] and then a tab command like [taa10:d] and then these email addresses:
[taa10:d]the_new_guy@somewhere.com[<]
[taa10:d]joe@aol.com[<]
[taa10:d]support@duxsys.com[<]
...DBT can make the text line up on the @ sign:
thescribe@somewhere.com
joe@aol.com
support@duxsys.com
Note: As with any tab alignment, one must take account of the maximum line width and the size of the text to be aligned when selecting the column position to align on, etc.