1

I'm trying to create:

 Hypothesis 1a
 Hypothesis 1b
 Hypothesis 2a
 Hypothesis 2b
 Hypothesis 3

I followed the code from an earlier thread, but instead of getting "Hypothesis 3", I get "Hypothesis 2c".

What should I do to get "Hypothesis 3"? Thanks so much for all your help.

\documentclass{article}
\usepackage{ntheorem}
\theoremindent1\parindent
\theoremseparator{:}
\newtheorem{theorem}{Hypothesis}
\usepackage{chngcntr}
\newcounter{pretheorem}
\counterwithin{theorem}{pretheorem}
\renewcommand\thetheorem{\arabic{pretheorem}\alph{theorem}}
\newcommand{\theoremgroup}{\refstepcounter{pretheorem}}
\begin{document}
\theoremgroup
    \begin{theorem}
        This is Hypothesis 1a
    \end{theorem}

    \begin{theorem}
        This is Hypothesis 1b
    \end{theorem}
\theoremgroup
    \begin{theorem}
        This is Hypothesis 2a
    \end{theorem}
    \begin{theorem}
        This is Hypothesis 2b
    \end{theorem}
\theoremgroup
    \begin{theorem}
        This is Hypothesis 3, but I'm getting Hypothesis 2c
    \end{theorem}
\end{document}
Mico
  • 506,678
sss123
  • 11

2 Answers2

1

You can adapt the code for subequations from amsmath. Since this is independent from ntheorem, I omit that part from the example; you can add the setting for the theorem.

\documentclass{article}

\newtheorem{hypothesis}{Hypothesis}

\makeatletter
\newcounter{parenthypothesis}
\newenvironment{subhypothesis}
 {
  \refstepcounter{hypothesis}%
  \protected@edef\theparenthypothesis{\thehypothesis}%
  \setcounter{parenthypothesis}{\value{hypothesis}}%
  \setcounter{hypothesis}{0}%
  \def\thehypothesis{\theparenthypothesis\alph{hypothesis}}%
  \ignorespaces
}{%
  \setcounter{hypothesis}{\value{parenthypothesis}}%
  \ignorespacesafterend
}
\makeatother

\begin{document}

\begin{subhypothesis}
\begin{hypothesis}
This is Hypothesis 1a
\end{hypothesis}

\begin{hypothesis}
This is Hypothesis 1b
\end{hypothesis}
\end{subhypothesis}

\begin{subhypothesis}
\begin{hypothesis}
This is Hypothesis 2a
\end{hypothesis}
\begin{hypothesis}
This is Hypothesis 2b
\end{hypothesis}
\end{subhypothesis}

\begin{hypothesis}
This is Hypothesis 3
\end{hypothesis}

\end{document}

enter image description here

egreg
  • 1,121,712
0

The code you've provided generates the number "3a" for the final hypothesis. If you want it to be numbered "3", i.e., without any suffix, you need to replace the final \theoremgroup directive with 

\counterwithout{theorem}{pretheorem}
Mico
  • 506,678