LyX ⇒ theorem numbering

[CSMR]

Hello. Liking LyX so far! (LyX 1.6RC3)
My first question is about theorem numbering.
I want theorem types: theorem, proposition, assumption, definition, corollary, lemma,...
I want them to be numbered independently.
When I use Theorems (AMS) and Theorems (AMS-Extended) they are numbered jointly (assumption 1, definition 2, theorem 3,...).
One solution would be to remove Theorems (AMS-Extended) and define my own. But that does not seem to be working.
Here is the code:

Code: Select all

\usepackage{amsthm}
\usepackage{amssymb}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
\numberwithin{equation}{section} %% Comment out for sequentially-numbered
\numberwithin{figure}{section} %% Comment out for sequentially-numbered
\theoremstyle{plain}
\theoremstyle{plain}
\newtheorem{thm}{Theorem}
  \theoremstyle{plain}
  \newtheorem{assumption}[thm]{Assumption}
  \theoremstyle{plain}
  \newtheorem{fact}[thm]{Fact}
  \theoremstyle{definition}
  \newtheorem{defn}[thm]{Definition}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% User specified LaTeX commands.
\newtheorem{userdefined}{Userdefined}

Because of the silly [thm] tags in the definitions the numbering is wrong. But that part is lyx-generated so I can't edit it.
The problem is my "\newtheorem{userdefined}{userdefined}" does not seem to be working: it doesn't seem to create the theorem class, despite looking just like the others in the latex code. (\theoremstyle makes no difference)

What is the solution?
Thanks!

[CSMR]

Any ideas?
How to change numbering system or how to define new theorem types?

[Juanjo]

I am not a LyX user, but after playing a bit with Lyx 1.5.6 (the last release on Mac), I think I can figure out which is your problem. Each class defines a series of theorem-like environments which can be easily accessed through the pulling menu on the top left corner of the window (together with standard, itemize, enumerate, part, section,...) Suppose that a given class provides the environments "Theorem" and "Lemma" sharing numbering. You cannot modify this... without tweeking inside the class file. At most, if numbering is reset in each section, you can get to reset it in each chapter or not to reset it at all in the whole document. Of course, you can define your own environments. The code appearing in your post for "userdefined" is correct and works. I don't know if it is possible to include user defined environments in the pulling menu. In any case, you can use it through ERT, writting, say:

Code: Select all

\begin{userdefined}This is my own theorem-like environment \end{userdefined}

This is not comfortable, but it works.

[CSMR]

Thanks for the info. That's unfortunate. Hopefully the menu issue will be fixed in a later version.

[Maksi]

I am not using the 1.6.x-version yet, but that sounds like something that will be much easier in the future thanks to layout modules…

[CSMR]

I am not using the 1.6.x-version yet, but that sounds like something that will be much easier in the future thanks to layout modules…

You may as well use 1.6; they have just released the windows installer for the 4th release candidate.
The problems were with the Theorems modules (standard, AMS, and extended), but probably can be fixed by editing these layout modules.