Numbering examples independently

newtheoremnumbering

I created a theorem command defining example sections, definitions, etc. the same way like so

\newtheorem{example}[thm]{\protect\examplename}

Of course, the numbering of this is consistent with the numbering of every other theorem command. For example, currently I would have something like this for the first section of the paper

Definition 1.

Definition 2.

Example 3.

But what I want is for the examples to be numbered independently by its section number and subsection (or even just by its section. As long as the numbering starts over from 1), like this

Definition 1.

Definition 2.

Example 1.1

Best Answer

Assuming you're using amsthm or compatible package (for some reason you didn't say), you can do this—

For Example 1.1 (by section number):

\newtheorem{example}{\protect\examplename}[section]

or for Example 1.1.1 (by subsection number):

\newtheorem{example}{\protect\examplename}[subsection]

Definitely don't add [thm] in the middle if you don't want the numbering to be shared with theorems. That's what that does.

Related Solutions

[Tex/LaTex] Theorem/Definition/Lemma problem — Numbering

Similar to the solution at this question and section 3 of the amsthm documentation:

enter image description here

\documentclass[11pt,a4paper]{report}
\usepackage{amsthm}

\theoremstyle{plain}
\newtheorem{thm}{Theorem}[chapter] % reset theorem numbering for each chapter

\theoremstyle{definition}
\newtheorem{defn}[thm]{Definition} % definition numbers are dependent on theorem numbers
\newtheorem{exmp}[thm]{Example} % same for example numbers

\newcommand{\chaptercontent}{
\section{Basics}
\begin{defn}Here is a new definition.\end{defn}
\begin{thm}Here is a new theorem.\end{thm}
\begin{thm}Here is a new theorem.\end{thm}
\begin{exmp}Here is a good example.\end{exmp}
\subsection{Some tips}
\begin{defn}Here is a new definition.\end{defn}
\section{Advanced stuff}
\begin{defn}Here is a new definition.\end{defn}
\subsection{Warnings}
\begin{defn}Here is a new definition.\end{defn}
}

\begin{document}
\tableofcontents
\part{Addition and Subtraction}
\chapter{Addition} \chaptercontent
\chapter{Subtraction} \chaptercontent
\part{Multiplication and Division}
\chapter{Multiplication} \chaptercontent
\chapter{Division} \chaptercontent
\end{document}

[Tex/LaTex] Theorem/Definition/Lemma problem — Numbering in Beamer

You need to number subsections within sections and theorems within sections, to achieve what you want.

\numberwithin{subsection}{section}
\numberwithin{theorem}{subsection}

Also, you need to declare

\setbeamertemplate{theorems}[numbered]

otherwise they are not numbered at all.

MWE:

\documentclass{beamer}

\setbeamertemplate{theorems}[numbered]
\numberwithin{subsection}{section}
\numberwithin{theorem}{subsection}

\begin{document}
\section{Functions}
\subsection{Basics}
\begin{frame}
\frametitle{A Theorem on Infinite Sets}
\begin{theorem}
There exists an infinite set.
\end{theorem}
\begin{proof}
This follows from the axiom of infinity.
\end{proof}
\begin{example}[Natural Numbers]
The set of natural numbers is infinite.
\end{example}
\end{frame}
\end{document}

enter image description here

Note that I haven't changed the fact that all theorem-like environments share the same counter.

Best Answer

Related Solutions

[Tex/LaTex] Theorem/Definition/Lemma problem — Numbering

[Tex/LaTex] Theorem/Definition/Lemma problem — Numbering in Beamer

Related Question