Changing Table Numbering Scheme to Include Section Number

Question

When I create a table and use \caption, Latex automatically adds "Table 1.1" or something similarly numbered. I'm using the book format, and want the caption numbering to be of the form "Table x.y.z", where x is the chapter number, y is the section number, and z is the table number within x.y. For example, the second table in section 4 in chapter 2 should say "Table 2.4.2".
How do I make Latex change the numbering of the tables?

Answer 1

Although your question is closely related to the following question, the numbering scheme you want is different.

• Continuous v. per-chapter/section numbering of figures, tables, and other document elements

The general solution is the same, however:

Use the chngcntr package to determine which counters depend on which. In your case, you want the table counter to depend on the section counter, so you add

\usepackage{chngcntr}
\counterwithin{table}{section}

Answer 2

For this two things are needed:

1. the table counter need resetting whenever the section counter is stepped
2. the command to display the counter value should show the combination of chapter, section and table.

You achieve the first by placing

\makeatletter
\@addtoreset{section}{table}
\makeatother

into the preamble of your document. The second step is done through

\renewcommand\thetable{\thesection.\arabic{table}}

where \thesection is the "display number" of the current section which in book is equiv to \arabic{chapter}.\arabic{section}.

When using amsmath

If you use the amsmath package the solution is even simpler as this packages offers a declaration that combines the above steps:

\numberwithin{table}{section}