Chapter count not increasing

Question

Consider the following MWE:

\documentclass[12pt,twoside,letterpaper]{report}

\usepackage{etoolbox}

\newcounter{totchapters}

\providecommand\totchap{}

\makeatletter
\AtEndDocument{%
  \addtocounter{totchapters}{\value{chapter}}%
  \immediate\write\@mainaux{%
    \string\gdef\string\totchap{\number\value{totchapters}}%
  }%
}
\makeatother

\pretocmd{\chapter}{\addtocounter{totchapters}{\value{chapter}}\setcounter{chapter}{0}}{}{}

\begin{document}
\totchap    \chapter{one}
\chapter{two}
\chapter{three}
\chapter{four}
\end{document}

I am trying to gain access to the total number of chapters in a document. I got inspiration from https://tex.stackexchange.com/a/55583/10898. But for some reason or the other the chapter counter is affected and no longer increasing. Why is that the case and how can it be fixed? Note that I would like to use this total to make calculations.

score 6 · Answer 1 · answered May 08 '13 at 21:38

6

The totcount does this without any redefinition.

\documentclass[12pt,twoside,letterpaper]{report}

\usepackage{totcount}
\regtotcounter{chapter}

\begin{document}
This document has \total{chapter} chapters.

\chapter{one}
\chapter{two}
\chapter{three}
\chapter{four}
\end{document}

The first page will show

This document has 4 chapters.

answered May 08 '13 at 21:38

egreg

1,121,712

Can you use \total{chapter} to make arithmetic calculations? – azetina May 08 '13 at 21:47
2

@azetina If you define \newcommand{\numtotal}[1]{\value{#1@totc}} you can use \numtotal{chapter} (or any other registered counter) in the context of a <number>. The returned value is -1 at the first run (totcount uses the .aux file for its workings). – egreg May 08 '13 at 22:04
@egreg Is there a way to have access to the total number of chapters per part? – pluton Jul 21 '13 at 02:50
@pluton This would be the subject for a new question – egreg Jul 21 '13 at 09:23

score 5 · Accepted Answer · answered May 08 '13 at 19:12

5

You can change the code to use \stepcounter{totchapters} rather than

\addtocounter{totchapters}{\value{chapter}}

Perhaps I have misunderstood the original intent, but here's a complete MWE that works as expected

% arara: pdflatex
\documentclass{report}

\usepackage{etoolbox}

\newcounter{totchapters}

\providecommand\totchap{}

\makeatletter
\AtEndDocument{%
  %\stepcounter{totchapters}%
  \immediate\write\@mainaux{%
    \string\gdef\string\totchap{\number\value{totchapters}}%
  }%
}
\makeatother

\pretocmd{\chapter}{\stepcounter{totchapters}}{}{}

\begin{document}
\totchap\
\chapter{one}
\chapter{two}
\chapter{three}
\chapter{four}
\end{document}

answered May 08 '13 at 19:12

cmhughes

100,947

Can I use \totchap in calculations? For example, 5/\totchap. – azetina May 08 '13 at 19:15
@azetina Is it possible to get the current item number and perform arithmetic on it in enumerate environment? – cmhughes May 08 '13 at 19:23
Something like \number\numexpr\totchap+3\relax I suppose. – azetina May 08 '13 at 19:27
Why using a new counter? Doesn't \immediate\write\@mainaux{\gdef\string\totchap{\number\value{chapter}} do the same? – egreg May 08 '13 at 22:22

Chapter count not increasing

2 Answers2