1

I'm writing about C* algebras and I'm trying to write *-strings efficiently. I managed to define C* like this:

\newcommand{\Cstar}{C\textsuperscript{*}}

While I have to invoke it as \Cstar{} to prevent it from sticking to the next word, I have had trouble writing a command to add * to any word (such as morphism or isometry). I tried doing this:

\newcommand{\star}[1]{#1\textsuperscript{*}}

without luck. Is this possible, and should I be doing this with LaTex, or is it something I should be doing with my editor's macros?

  • Welcome to TeX.SX! Note that it is usually best practice here to include a small example document that does only include the bare necessities to show what you're trying so far (e.g. \documentclass{article}\newcommand\star[1]{#1\textsuperscript{*}}\begin{document}\star{Foo}\end{document} would suffice here). – Skillmon Apr 8 at 19:59
  • 1
    The command \star is already defined in LaTeX. You can try \Star instead. – Phelype Oleinik Apr 8 at 20:00
0

In my opinion, the asterisk should be always in the upright font, independently of the context. Besides, \textsuperscript{*} would place the asterisk too high, see the last line in the image below.

Also C* should probably always appear upright, but you may decide otherwise.

Redefining \star could be safe in your context, but be aware that \star is the name of a symbol, namely ⋆, and you may want to save it under another name in case you decide to use it.

\documentclass{article}
\usepackage{amsmath}

\newcommand{\Star}[1]{#1\ensuremath{^*}\kern-\scriptspace}
\newcommand{\CStar}{\Star{\ensuremath{\mathrm{C}}}}

\begin{document}

% the commands in upright text
We deal with \CStar-algebras, with \Star{morphisms}
and \Star{isometries}.

% the commands in italics context, such as theorems
\textit{We deal with \CStar-algebras, with \Star{morphisms}
and \Star{isometries}.}

% with \textsuperscript{*}
\textit{We deal with C\textsuperscript{*}-algebras, with morphisms\textsuperscript{*}
and isometries\textsuperscript{*}.}

\end{document}

enter image description here

  • Thank you, the upgright text is just what I was looking for. – user20402 Apr 8 at 21:09

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.