What you need to know first: the basics about Using Tab Alignment. Also, it might help to review the Notes on General Code Syntax.
Please, do not be put off by the term "decimal". This form of alignment places decimal numbers in columns aligned on the decimal point, but it is more flexible than that implies. In DBT, this alignment option can be used to align text or numbers on any specified character, a term we might perhaps call "Designated Character Alignment".
Codes Used: [svdac~x] defines the decimal character, prior to using [taa] or [tab] or combination of [stb] and [#S] to perform a decimal tab alignment.
See also: [ifbrl] and [ifprt]
What does it do?
The svdac code allows you to specify what character is to be used to align numbers or even text.
Where would it be used?
Many countries write numbers with commas separating the thousands, and a period or full stop as the decimal point. For example: 7,134.56 as done in America and the U.K.
However, in much of Europe the format is reversed, and therefore in the above example, it would be written as 7.124,56
How does it work?
[svdac~X] - Set decimal alignment character to X. This sets the character that is used by the tab commands to control decimal alignment. The default is the character that is common for American usage, i.e., [svdac~.], for both print and braille files (which produces dots 4-6 in the latter).
In addition, the codes [ifbrl] and [ifprt] can be used to insert svdac twice, once to define a braille decimal character and to define a print decimal character.
For the more technical:
This would be an ideal code to include in the initial style of a template to set the decimal character.