73

amsthm has three separate predefined styles: \theoremstyle{plain} is the default. it sets the text in italic and adds extra space above and below the \newtheorems listed below it in the input. it is recommended for theorems, corollaries, lemmas, propositions, conjectures, criteria, and (possibly; depends on the subject area) algorithms. \theoremstyle{...


73

Similar to the solution at this question and section 3 of the amsthm documentation: \documentclass[11pt,a4paper]{report} \usepackage{amsthm} \theoremstyle{plain} \newtheorem{thm}{Theorem}[chapter] % reset theorem numbering for each chapter \theoremstyle{definition} \newtheorem{defn}[thm]{Definition} % definition numbers are dependent on theorem numbers \...


58

The thm-restate package which is part of thmtools offers a restatable environment. In the following example, I also use hyperref and cleveref (its \cref macro automatically adds the correct theorem type). See section 1.4 of the thmtools manual for details. \documentclass{article} \usepackage{thmtools} \usepackage{thm-restate} \usepackage{hyperref} \...


54

An easy way is \documentclass{article} %\usepackage{amsthm} %% uncomment to see the difference \newtheorem{innercustomthm}{Theorem} \newenvironment{customthm}[1] {\renewcommand\theinnercustomthm{#1}\innercustomthm} {\endinnercustomthm} \begin{document} \begin{customthm}{8}\label{eight} Every theorem must be numbered by hand. \end{customthm} Here is a ...


48

The documentation of amsthm says: A QED symbol, □, is automatically appended at the end of a proof environment. To substitute a different end-of-proof symbol, use \renewcommand to redefine the command \qedsymbol. Thus, one might proceed as follows: \renewcommand{\qedsymbol}{$\blacksquare$} A mwe to play with: \documentclass[a4paper,11pt]{article} \...


35

exe is a LaTeX counter, and \theexe is a macro for formatting/displaying the current value of the counter (and is by default set to \arabic{exe}). Redefining \theexe with \renewcommand will not change the underlying counter, and redefining it to always be 0 will cause all values of the counter to be displayed as zero. Instead, you should be using the LaTeX ...


34

You need to redefine \proofname: \documentclass{amsbook} \usepackage{amsthm} \renewcommand*{\proofname}{Solution} \begin{document} \begin{proof} This is a solution. \end{proof} \end{document}


34

The \newtheorem command has two mutually exlusive optional arguments: Using \newtheorem{<name>}{<heading>}[<counter>] will create an environment <name> for a theorem-like structure; the counter for this structure will be subordinated to <counter>. On the other hand, using \newtheorem{<name>}[<counter>]{<...


34

Assuming you're using a package such as amsthm, you could proceed as follows: Assign a \label to the theorem, and then cross-reference it via a \ref statement at the start of the associated proof environment. \documentclass{article} \usepackage{amsthm} \usepackage{lipsum} % for filler text \newtheorem{theorem}{Theorem} \begin{document} \begin{theorem}[...


33

The "official" AMS suggestion, presented in a FAQ entry, is to follow \begin{thm} with the command \leavevmode. this will leave the theorem header on a line by itself. edit: the amsthm documentation has undergone a thorough revision. the new version (amsthdoc.pdf) is on ctan and will be included in tex live 2015. more "elaborate" possibilities are ...


32

You can put this in the preamble, without the need to define new theorem styles; in fact this redefines the plain and definition theorem styles in order that the theorem title has the same font attributes as the theorem heading: \usepackage{amsthm} \makeatletter \def\th@plain{% \thm@notefont{}% same as heading font \itshape % body font } \def\th@...


32

You can set the theorems template with the numbered option: \setbeamertemplate{theorems}[numbered] or with the ams style option: \setbeamertemplate{theorems}[ams style] If additionally you use the envcountsect class option by loading beamer in the following way: \documentclass[envcountsect]{beamer} then theorems, definitions, and so on to be numbered ...


32

Just locally change the meaning of \qedsymbol: \documentclass{article} \usepackage{amsthm} \begin{document} \begin{proof} This has the QED symbol. \end{proof} \begin{proof}\renewcommand{\qedsymbol}{} This hasn't. \end{proof} \begin{proof} And this has it again. \end{proof} \end{document} You can make a new environment for "inner proofs": \newenvironment{...


31

Ad-hoc restyling can be done using \normalfont at the start of the definition: \documentclass{article} \newtheorem{definition}{Definition} \begin{document} \begin{definition} Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed eu eros dignissim mi ultricies varius in ac purus. Mauris et massa turpis. Aenean egestas fringilla odio, in placerat ...


30

If the QED symbol (or tombstone) is needed only rarely, I suggest to use the \qedhere feature provided by amsthm. \documentclass{article} \usepackage{amsthm} \newtheorem{thm}{Theorem} \begin{document} \begin{thm} Some text some text some text some text some text some text some text some text some text some text some text some text some text some text some ...


29

The amsmath package provides the command numberwithin- it can be used as demonstrated in the MWE below. Note that the numberwithin command can be used on pretty much any environment that has a number (tables, figures, etc). \documentclass{report} \usepackage{amsmath} % provides numberwithin (and lots more) \usepackage{lipsum} % for sample text \...


28

beamer uses translator to translate environment names and some other words. It uses some .dict files which you can translate to your language and start to use. Look at manual's section Translating strings. Here you have a little example. \documentclass{beamer} \uselanguage{spanish} \languagepath{spanish} \deftranslation[to=spanish]{Theorem}{Teorema} \...


26

You can use \newmdtheoremenv from the mdframed package: \documentclass{article} \usepackage{mdframed} \usepackage{lipsum} \newmdtheoremenv{theo}{Theorem} \begin{document} \begin{theo} \lipsum*[1] \end{theo} \end{document} If you only want to frame some theorems, then you can define a new environment using the mdframed environment and some previously ...


26

Use the \emph command to emphasize a word. Normally, this will italicize the word, but if you are already in italics mode, it will do the opposite.


25

With the theorem packages you would normally use \qed or \qedhere. Without those you use the commands below depending on if you want the filled square or empty: \documentclass[border=2pt]{standalone} \usepackage{amssymb} \newcommand*{\QEDA}{\hfill\ensuremath{\blacksquare}}% \newcommand*{\QEDB}{\hfill\ensuremath{\square}}% \begin{document} Lorem ipsum \...


25

if you are using amsthm or an ams document class, this problem is addressed by an item in the ams author faq. this in turn links to an example document that covers quite a few of the possible situations in which such a marker could be wanted. the most extreme situations require some manual effort, but i believe that nearly all reasonable possibilities (...


25

There is a bug in thm-autoref.sty. Part of the set-up for cleverefs magic is left to the start of the document. So cleveref maintains a list of all the label types that it has been told about so that when it gets to the \begin{document} hook, it can iterate through them and finish the necessary configuration. Examining this list for your document (well, ...


24

this is a "break" style recommended in the ams' "newtheorem and theoremstyle test" for amsthm: \newtheoremstyle{break}% name {}% Space above, empty = `usual value' {}% Space below {\itshape}% Body font {}% Indent amount (empty = no indent, \parindent = para indent) {\bfseries}% Thm head font {.}% Punctuation after ...


23

Loop Space's answer is good, but has the disadvantage of clobbering the optional argument, so attribution can't be specified any more. I'd suggest using a mandatory argument. \documentclass{article} \usepackage{amsthm} \swapnumbers % optional, of course \newtheorem{thm}{Theorem}[section] % the main one \newtheorem{lemma}[thm]{Lemma} % other statement ...


23

I don't know if the tcolorbox package was available at the time that the question was asked, but here's a small example taken directly from the documentation: % arara: pdflatex \documentclass{article} \usepackage{tcolorbox} \tcbuselibrary{theorems} \newtcbtheorem[number within=section]{mytheo}{My Theorem}% {colback=green!5,colframe=green!35!black,...


23

You can use the thmtools package as a front-end to amsthm; adding the end marks is then an easy matter: \documentclass{book} \usepackage{amssymb} \usepackage{amsthm} \usepackage{thmtools} \declaretheorem[style=definition,qed=$\blacksquare$,numberwithin=chapter]{definition} \declaretheorem[style=definition,qed=$\blacktriangle$,sibling=definition]{example} \...


23

The optional argument of \cite & friends is mostly used for page numbers, but references to chapters/sections, paragraphs, verses etc. are not unheard of. Assuming that a declaration like "Proposition 3.iii" will refer to a unique location in your source, there's nothing wrong in using \cite[Proposition~3.iii]{<source>}. (One may still add the page ...


23

The answer depends on the package used to declare the theorem-like structures. If you are using the ntheorem package, you can simply use the predefined break style: \documentclass{article} \usepackage{ntheorem} \usepackage{lipsum} \theoremstyle{break} \newtheorem{theorem}{Theorem} \begin{document} \begin{theorem}[Some note] \lipsum*[2] \end{theorem} \...


23

The model I used is that of the subequations environment in amsmath: \documentclass{article} \makeatletter \newenvironment{subtheorem}[1]{% \def\subtheoremcounter{#1}% \refstepcounter{#1}% \protected@edef\theparentnumber{\csname the#1\endcsname}% \setcounter{parentnumber}{\value{#1}}% \setcounter{#1}{0}% \expandafter\def\csname the#1\endcsname{\...


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