Different counters for theorems, lemmas, definitions,

lemmatheorems

I don't know how I can create different counters for theorems, lemmas, definitions, observations, corollaries, examples and exercises.
I'd like to have the numeration of these as chapter.section.subsection.number, where "number" stays for the number of theorem, lemma, … .
For example I'd like to have something like that:

Theorem (Pytagora) — 1.1.1.1,

Lemma (Zorn) — 1.1.1.1,

Theorem (Cayley–Hamilton) — 1.1.1.2,

Corollary (of Theorem 1.1.1.2) — 1.1.1.2.a,

Definition (Cauchy's succession) — 1.1.1.1.

I hope in you help, Thank you so much
Best Regards

Best Answer

I answer my question:

\documentclass{book}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{mathtools}
\usepackage{amsthm}
\usepackage{stix}

%(Re)newcommands

\renewcommand\qedsymbol{$\blacksquare$}

%New 8 counters

\newtheorem{theorem}{Theorem}[subsection]

\newtheorem{definition}{Definition}[subsection]

\newtheorem{lemma}{Lemma}[subsection]

\newtheorem{corollary}{Corollary}[subsection]

\newtheorem{proposition}{Proposition}[subsection]

\newtheorem{example}{Example}[subsection]

\newtheorem{exercise}{Exercise}[subsection]

\newtheorem{observation}{Observation}[subsection]

%New Theorems

\newcommand{\namedtheoremname}{}
\newtheorem{namedtheoreminner}[theorem]{\protect\namedtheoremname}
\newenvironment{namedtheorem}[1]
{%
\renewcommand{\namedtheoremname}{#1}%
\begin{namedtheoreminner}%
}
{\end{namedtheoreminner}}

%New Definitions

\newcommand{\nameddefinitionname}{}
\newtheorem{nameddefinitioninner}[definition]{\protect\nameddefinitionname}
\newenvironment{nameddefinition}[1]
{%
\renewcommand{\nameddefinitionname}{#1}%
\begin{nameddefinitioninner}%
}
{\end{nameddefinitioninner}}

%New Lemmas

\newcommand{\namedlemmaname}{}
\newtheorem{namedlemmainner}[lemma]{\protect\namedlemmaname}
\newenvironment{namedlemma}[1]
{%
\renewcommand{\namedlemmaname}{#1}%
\begin{namedlemmainner}%
}
{\end{namedlemmainner}}

%New Corollaries

\newcommand{\namedcorollaryname}{}
\newtheorem{namedcorollaryinner}[corollary]{\protect\namedcorollaryname}
\newenvironment{namedcorollary}[1]
{%
\renewcommand{\namedcorollaryname}{#1}%
\begin{namedcorollaryinner}%
}
{\end{namedcorollaryinner}}

%New Propositions

\newcommand{\namedpropositionname}{}
\newtheorem{namedpropositioninner}[proposition]{\protect\namedpropositionname}
\newenvironment{namedproposition}[1]
{%
\renewcommand{\namedpropositionname}{#1}%
\begin{namedpropositioninner}%
}
{\end{namedpropositioninner}}


%New Examples

\newcommand{\namedexamplename}{}
\newtheorem{namedexampleinner}[example]{\protect\namedexamplename}
\newenvironment{namedexample}[1]
{%
\renewcommand{\namedexamplename}{#1}%
\begin{namedexampleinner}%
}
{\end{namedexampleinner}}


%New Exercises

\newcommand{\namedexercisename}{}
\newtheorem{namedexerciseinner}[exercise]{\protect\namedexercisename}
\newenvironment{namedexercise}[1]
{%
\renewcommand{\namedexercisename}{#1}%
\begin{namedexerciseinner}%
}
{\end{namedexerciseinner}}

%New Observations

\newcommand{\namedobservationname}{}
\newtheorem{namedobservationinner}[observation]{\protect\namedobservationname}
\newenvironment{namedobservation}[1]
{%
\renewcommand{\namedobservationname}{#1}%
\begin{namedobservationinner}%
}
{\end{namedobservationinner}}



\title{Theorem Proof, Stack}

\author{Name, Surname}
\begin{document}

\maketitle

\chapter{First Chapter}

\section{Theorems}
\subsection{Theorems}
\begin{namedtheorem}{First Theorem}
Statement.
\end{namedtheorem}
\begin{proof}
Its Proof.
\end{proof}

\begin{nameddefinition}{First Definition}

\end{nameddefinition}

\begin{nameddefinition}{Second Definition: Cauchy's Succession}
\end{nameddefinition}

\begin{namedlemma}{Zorn's Lemma}
Statement.
\begin{proof}
Its Proof.
\end{proof}
\end{namedlemma}

\end{document}

Observe this:

%New 8 counters

\newtheorem{theorem}{Theorem}[subsection]

\newtheorem{definition}{Definition}[subsection]

\newtheorem{lemma}{Lemma}[subsection]

\newtheorem{corollary}{Corollary}[subsection]

\newtheorem{proposition}{Proposition}[subsection]

\newtheorem{example}{Example}[subsection]

\newtheorem{exercise}{Exercise}[subsection]

\newtheorem{observation}{Observation}[subsection]

In this way it is possible create new counters and then use themselves like so:

% This is the main template for particular \LeTeX--Functions %

\newcommand{\namednewcountername}{}
\newtheorem{namednewcounterinner}[newcounter]{\protect\namednewcountername}
\newenvironment{namednewcounter}[1]
{%
\renewcommand{\namednewcountername}{#1}%
\begin{namednewcounterinner}%
}
{\end{namednewcounterinner}}

Here You can substutuite newcounter with theorem, lemma, proposition, ... .

THANK YOU

Related Solutions

[Tex/LaTex] Theorem numbering

When using either the ntheorem or the amsthm package to declare theorem-like environments, it's important to make use of the following rules of syntax when using \newtheorem:

If you want the counter of a theorem-like environment to be subordinate to, say, the section number, use a directive such as
```
\newtheorem{theorem}{Theorem}[section]
```
i.e., the option [section] (the name of the "parent counter") should come at the end.
If, on the other hand, you want the theorem-like environment (say, corollary) to share a counter with an already-existing environment (say, theorem), use the following syntax:
```
\newtheorem{corollary}[theorem]{Corollary}
```
i.e., i..e, the option [theorem] (the name of the "shared counter") should be placed between the environment name and the way the environment's name should be typeset.

The output of a full MWE:

\documentclass{article}  
\usepackage{ntheorem}

\theoremstyle{theorem} 
   \newtheorem{theorem}{Theorem}[section]
   \newtheorem{corollary}[theorem]{Corollary}
   \newtheorem{lemma}[theorem]{Lemma}
   \newtheorem{proposition}[theorem]{Proposition}
\theoremstyle{definition}
   \newtheorem{definition}[theorem]{Definition}
   \newtheorem{example}[theorem]{Example}
\theoremstyle{remark}    
  \newtheorem{remark}[theorem]{Remark}

\begin{document}
\setcounter{section}{1}

\begin{theorem} a \end{theorem}
\begin{proposition} b \end{proposition}
\begin{definition} c \end{definition}
\begin{example} d \end{example}
\begin{remark} e \end{remark}
\begin{lemma} f \end{lemma}

\end{document}

Index for Equations, Definitions, Theorems,

For everything except equations, if you define them as "theorem" environments, you can load thmtools and use the \listoftheorems command.

See the documentation (https://ctan.org/pkg/thmtools?lang=en) for how to filter the listing by type.

Listing equations have been asked several times previously on this site, the first one I found is List of Equations / Table of Equations

Best Answer

Related Solutions

[Tex/LaTex] Theorem numbering

Index for Equations, Definitions, Theorems,

Related Question