new command for the dx of intergral. [duplicate]

Possible Duplicate:
What’s the proper way to typeset a differential operator?

\newcommand{d}[1]{\:\textrm{d}{#1}}


That is my new comamnd for writing the dx of an intergral. Just wanted to be able to type this in my code.

\d{x}  <<<where the x is the variable of integration>>>


What did I do wrong?

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Related Question: Should I \mathrm the d in my integrals? –  Peter Grill Nov 17 '12 at 7:56

marked as duplicate by Claudio Fiandrino, Thorsten, Andrew Swann, Stephen, Martin SchröderDec 18 '12 at 18:30

\newcommand\d[1]{\:\textrm{d}#1}
\renewcommand\d[1]{\:\textrm{d}#1} % if \d is already defined


only for a definition of an environment you use \newenvironment{env}. Another useful definition is:

\newcommand*\diff{\mathop{}\!\mathrm{d}}


in your definition you do not really need the argument and using \mathrm makes more sense, then it takes the d from the same math font and not from the text font

\documentclass{article}
\renewcommand\d[1]{\:\textrm{d}#1}
\newcommand*\diff{\mathop{}\!\mathrm{d}}
\begin{document}
$\d x \textrm{ or } \diff x$
\end{document}

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Ok. uh. so what do I type in the body? –  MaoYiyi Nov 17 '12 at 7:49
\d{x} or \d x or \diff x –  Herbert Nov 17 '12 at 7:52
@MaoYiyi: You should not use \d as that is already used elsewhere. –  Peter Grill Nov 17 '12 at 7:53
@Herbert that didn't work. –  MaoYiyi Nov 17 '12 at 7:57
@MaoYiyi: sure makes no difference –  Herbert Nov 17 '12 at 8:17