Cfrgtkky

I'm writing some notes and I have a problem with the organization. I defined the theorems as follows:

documentclass[12pt,a4paper]{book}



theoremstyle{plain}

newtheorem{teo}{Teorema}[chapter]

newtheorem{theo}[teo]{Theorem}

newtheorem{coro}[teo]{Corolary}

newtheorem{lema}[teo]{Lemma}

newtheorem{prop}[teo]{Proposition}



theoremstyle{definition}

newtheorem{df}[teo]{Definition}

newtheorem{ex}[teo]{Example}

newtheorem{obs}[teo]{Remark}



begin{document}



end{document}

In the text, theorems, definitions, propositions etc are in the same "counter". I mean

Theorem 1.5

Proposition 1.6

Example 1.7

I want to organize as follows:

documentclass[12pt,a4paper]{book}



theoremstyle{plain}

newtheorem{teo}{Teorema}[chapter]

newtheorem{theo}[teo]{Theorem}

newtheorem{coro}[teo]{Corolary}

newtheorem{lema}[teo]{Lemma}

newtheorem{prop}[teo]{Proposition}



theoremstyle{definition}

newtheorem{df}[teo]{Definition}

newtheorem{ex}[teo]{Example}

newtheorem{obs}[teo]{Remark}



begin{document}



chapter{ONE}



  section{1}



     Proposition 1

     Theorem 1



  section{2}



     Theorem 2

     Example 1



chapter{TWO}



  section{1}



     Proposition 1

     Theorem 1



  section{2}



     Theorem 2

     Example 1





end{document}

Is it possible to do that?

Here you are: remove the optional [teo] everywhere, replace the optional [section]with[chapter], and redefinetheteo`, &c., so it doesn't include the chapter number as a prefix.

documentclass[12pt,a4paper]{book}

usepackage{amsthm}

theoremstyle{plain}

newtheorem{teo}{Teorema}[chapter]

newtheorem{theo}{Theorem}[chapter]

newtheorem{coro}{Corollary}[chapter]

newtheorem{lema}{Lemma}[chapter]

newtheorem{prop}{Proposition}[chapter]



renewcommand{theteo}{arabic{teo}}

renewcommand{thetheo}{arabic{theo}}

renewcommand{thecoro}{arabic{coro}}

renewcommand{thelema}{arabic{lema}}

renewcommand{theprop}{arabic{prop}}



theoremstyle{definition}

newtheorem{df}{Definition}[chapter]

newtheorem{ex}{Example}[chapter]

newtheorem{obs}{Remark}[chapter]

renewcommand{thedf}{arabic{df}}

renewcommand{theex}{arabic{ex}}

renewcommand{theobs}{arabic{obs}}



begin{document}



chapter{ONE}



  section{1}

    begin{prop}

         Proposition 1

    end{prop}

     begin{theo}

     A first theorem

    end{theo}



  section{2}



     begin{theo}

     Another theorem

    end{theo}

    begin{ex}

      A funny example.

    end{ex}



chapter{TWO}



  section{1}



    begin{prop}

         Another proposition.

    end{prop}



     begin{theo}

     A first theorem in chap. two

    end{theo}



  section{2}



     begin{theo}

     A second theorem in chap. two

    end{theo}

    begin{ex}

      A silly example.

    end{ex}



end{document}