[Tex/LaTex] Using chapter instead of section number with amsthm

amsthmnumberingtheorems

I'm trying to number my examples, definitions, theorems, etc. in the form Chapter#.example#.
However, the amsthm package only seems to provide sectional numbering, which I don't like.

Does anyone know how to get the correct format of numbering?

In the MWE the numbering should be: Example 1.1. and Definition 1.1.

\documentclass{book}
\usepackage{amsthm}
\newtheorem{exmp}{Example}
\newtheorem{defi}{Definition}[section]
\begin{document}
    \chapter{}
        \section{section 1}
        \begin{exmp}
        \end{exmp}
        \section{section 2}
        \begin{defi}
        \end{defi}
\end{document}

EDIT: I read this might be possible with thmtools, but i'd prefer to do it without loading additional packages if possible. Unless it becomes a to complicated solution ofcourse.

Best Answer

Although the manual doesn't explicitly say so, the following works:

\newtheorem{exmp}{Example}[chapter]
\newtheorem{defi}{Definition}[chapter]

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] Numbering theorems as subsubsections

Use the first optional argument for \newtheorem:

\documentclass{book}
\usepackage{amsthm}

\newtheorem{theo}[subsubsection]{Theorem}
\newtheorem{defi}[subsubsection]{Definition}
\setcounter{secnumdepth}{3}

\begin{document}

\chapter{Test Chapter}
\section{Test Section}
\subsection{Test Subsection}
\subsubsection{Test Subsubsection}
\begin{theo}
test.
\end{theo}
\subsubsection{Test Subsubsection}
\begin{theo}
test.
\end{theo}
\begin{defi}
test.
\end{defi}
\subsubsection{Test Subsubsection}

\end{document}

enter image description here

I think this numbering schema can result hard to follow for readers (among other things, what if, for example, there's a theorem or a definition before a subsubsection is created?).

For the bonus point (and to make things even harder for the reader):

\documentclass{book}
\usepackage{amsthm}
\usepackage{amsmath}
\usepackage{etoolbox}
\numberwithin{equation}{subsection}

\newtheorem{theo}[subsubsection]{Theorem}
\newtheorem{defi}[subsubsection]{Definition}
\setcounter{secnumdepth}{3}

\AtBeginEnvironment{equation}{\setcounter{equation}{\value{subsubsection}}}{}{}{}
\AtEndEnvironment{equation}{\stepcounter{subsubsection}}{}{}{}

\begin{document}

\chapter{Test Chapter}
\section{Test Section}
\subsection{Test Subsection}
\subsubsection{Test Subsubsection}
\begin{theo}
test.
\end{theo}
\subsubsection{Test Subsubsection}
\begin{theo}
test.
\end{theo}
\begin{defi}
test.
\end{defi}
\begin{equation}
a=b.
\end{equation}
\subsubsection{Test Subsubsection}
\begin{equation}
c=d.
\end{equation}

\end{document}

enter image description here

I would rather use a simpler numbering schema:

\documentclass{book}
\usepackage{amsthm}
\usepackage{amsmath}

\newtheorem{theo}{Theorem}[chapter]
\newtheorem{defi}[theo]{Definition}
\newtheorem{prop}[theo]{Proposition}
\setcounter{secnumdepth}{3}

\begin{document}
...
\end{document}

Best Answer

Related Solutions

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

[Tex/LaTex] Numbering theorems as subsubsections

Related Question