2

For theorems in my contribution I use \theoremstyle{plain}. This style prints theorem label in bold italics, eg. 'Theorem 1.', which is followed by text in italics. How could I set 'Theorem 1.' to italics to match the theorem content?

I read related question

Non italic text in theorems, definitions, examples

but I was not able to extract the answer.

  • 1
    See tex.stackexchange.com/a/38264/5626 and change \itshape to \itshape\bfseries (and other settings accordingly). But first of all: why on earth would you want to do that!? – mbork Jun 30 '12 at 11:45
  • Thanks. 1) I don't like bold up followed by italics, so I set everything to italics. 2) if 1) makes no sense, I simply don't like present scheme. – boy Jun 30 '12 at 11:50
2

This might be the theorem scheme that you're after, called mytheorem:

enter image description here

\documentclass{article}
\usepackage{lipsum}% http://ctan.org/pkg/lipsum
\usepackage{amsthm}% http://ctan.org/pkg/amsthm
\makeatletter
\newtheoremstyle{mytheorem}% <name>
  {3pt}% <Space above>
  {3pt}% <Space below>
  {\itshape}% <Body font>
  {}% <Indent amount>
  {\itshape\bfseries}% <Theorem head font>
  {.}% <Punctuation after theorem head>
  {.5em}% <Space after theorem heading>
  {\thmname{#1}\thmnumber{\@ifnotempty{#1}{ }#2}%
   \thmnote{ {\the\thm@notefont(#3)}}}% <Theorem head spec (can be left empty, meaning `normal')>
\makeatother
\theoremstyle{mytheorem}
\newtheorem{theorem}{Theorem}
\begin{document}
\begin{theorem}\lipsum[1]\end{theorem}
\end{document}

The key here is to include a theorem head specification (argument #9) in order to reformat the theorem number from \textup (or \@upn) to plain. Here's the default definition of the theorem head specification (associated with the plain style):

\def\thmhead@plain#1#2#3{%
  \thmname{#1}\thmnumber{\@ifnotempty{#1}{ }\@upn{#2}}%
  \thmnote{ {\the\thm@notefont(#3)}}}

Note the forced \@upn (defined as \textup).

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.