Start chapter numbers with 1 in every new part of document

Question

I'm using André Miede's classicthesis for Lyx. However, I couldn't figure out how to globally reset the chapter number after the start of a new part. This is how the TOC looks right now:

• Part 1
  • 1 Chapter
  • 1 Chapter
• Part 2
  • 3 Chapter

But I want it to look like this:

• Part 1
  • 1 Chapter
  • 1 Chapter
• Part 2
  • 1 Chapter

Every help is appreciated! Thanks a lot in advance!

Answer 1

You could add \@addtoreset{chapter}{part} to your preamble to add the chapter to the list of counters which are reset at the start of a new part

\documentclass{book}

\usepackage{classicthesis}

\makeatletter
\@addtoreset{chapter}{part}
\makeatother

\begin{document}

\tableofcontents

\part{title 1}

\chapter{title}
\chapter{title}
\chapter{title}

\part{title 2}

\chapter{title}
\chapter{title}
\chapter{title}
\chapter{title}
\chapter{title}

\end{document}

Answer 2

You just have to reset the proper counter at the start of a part.

For instance:

\newcommand{\mypart}[1]{\setcounter{chapter}{0} % reset chapter counter
                         \part{#1}              % then create the part
}

Then you can simply use \mypart instead of \part and the numbering will be as you wish.