General ⇒ Counter for defined environment

[Emonk]

Hi all,

I have an environment in my LaTeX code:

Code: Select all

\newenvironment{exercise}[1]
{\par \noindent \newline \newline \line(1,0){360} \\ \textbf{Exercise #1} \begin{itshape}\\}
{\\ \end{itshape} \line(1,0){360}}

I can call the environment by:

Code: Select all

\begin{exercise}{exercise_number}Contents\end{exercise}

But: I now have 18 exercises, and what if I want to paste in an exercise after exercise 7? Than I'll have to renumber al exercises after number 7! Is there an easy way to insert a counter, that I don't have to send the number of the exercise? Just like this:

Code: Select all

\begin{exercise}Contents\end{exercise}

Note: my English is very bad, please use easy words

Thanks!

[localghost]

You do not need to reinvent the wheel. It's so much easier (and smarter) to use the ntheorem package. Study its manual to learn more.

Code: Select all

\documentclass[11pt,a4paper,english]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{babel}
\usepackage{ntheorem}

\theoremstyle{break}
\theoremprework{\hrule}
\theorempostwork{\hrule}
\newtheorem{exercise}{Exercise}

\begin{document}
  \begin{exercise}
    Text
  \end{exercise}
\end{document}

And by the way, please always provide a minimal example that is compilable as provided for others.


Best regards and welcome to the board
Thorsten

[Emonk]

Very much thanks!
I now have added this code:

Code: Select all

\usepackage{ntheorem}
\theoremstyle{break}
\theoremprework{\hrule}
\theorempostwork{\hrule}
\newtheorem{exercise2}{Exercise}

But I get the error:

! LaTeX Error: Command \theoremstyle already defined.
Or name \end... illegal, see p.192 of the manual.

See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...

l.76 }

?

[localghost]

As already said, reduce the problem to a complete but minimal example. It has to contain only necessary code and must be compilable as provided. Could be that the digit in the name of the new theorem causes trouble. Have you tested my example?

[Emonk]

Yes, and now it's working. THANKS!