Counters

As you’ve seen in last chapter, LaTeX automatically keeps separate counters for every type of section. What’s really nice is that it does the same for nearly everything—tables, figures, table of contents, and so on. Because this concept of counters keeps popping up everywhere within LaTeX, I wanted to do a chapter on it here that explains how to customize them. Or maybe even add your own.

Setting & Getting Counters

To set an existing counter, use

1\setcounter{counter}{value}

To get the current value of a certain counter, as text, use

1\thecounter

1\setcounter{section}{4} 
2
3The value is: \thesection

If you don’t want it as text, but as a number to use in calculations, use \value{counter}.

Changing Counters

To increment an existing counter by a certain amount, use

1\addtocounter{counter}{value}

This value can be negative, if you want to decrement it.

To create a new counter, use

1\newcounter[counter]{name}

If you supply the optional argument counter, which must be an existing counter, this new counter is reset every time counter is changed.

Changing the Numbering System

It’s possible to display your counters using a different system than the regular Arabic numbers you’re used to.

1\newcounter{mysections}
2\addtocounter{mysections}{2}
3
4\section*{\Roman{mysections} A Section Numbered Differently} 
5Lorem Ipsum...

Useful Counters to Remember

By default, the table of contents only registers sections to a maximum of three levels deep. To set this to something else, change the counter tocdepth.

By default, all sections are numbered to a depth of 2—so, for example, sections and subsections are numbered, but subsubsections aren’t. To change this, use the counter secnumdepth.

1\setcounter{secnumdepth}{4}
2
3\section{La}
4\subsection{Lala}
5\subsubsection{Lalala}
6\paragraph{Lalalala}

All other counters are accessed by simply typing its name, as we’ve already seen with section.

Use \pagenumbering{numbering system} if you just want to change the numbering system of the current page.