Is there a convenient way to typeset the floor or ceiling of a number, without needing to separately code the left and right parts? For example, is there some way to do $\ceil{x}$ instead of $\lceil x \rceil$?
144
183
\usepackage{mathtools}
\DeclarePairedDelimiter{\ceil}{\lceil}{\rceil}
The command \ceil will do; if called as \ceil*{x} it will add \left and \right; you can also call it as
\ceil[\big]{x} \ceil[\Big]{x} \ceil[\bigg]{x} \ceil[\Bigg]{x}
to state explicitly the size of the delimiters.
-
20Even after more than 10 years of LaTeXing one still learns some new tricks! – yo' Jan 25 '12 at 17:32
-
12
-
1@jamaicanworm There is, I believe also on this site. But I won't tell you: use
\leftand\rightonly when they are really needed. – egreg Apr 21 '12 at 17:50 -
2@jamaicanworm Swap definition of starred and non-starred command discusses switching the starred with non-starred version. – Qrrbrbirlbel Nov 11 '12 at 1:36
-
6To typeset the floor function, just replace "ceil" with "floor". This may be obvious, but it might save you the trouble of consulting documentation. – void-pointer Sep 30 '13 at 7:19
17
Here is a simple xparse implementation of \ceil, similar to that provided by mathtools' \DeclarePairedDelimiter:
\documentclass{article}
\usepackage{xparse}% http://ctan.org/pkg/xparse
\NewDocumentCommand{\ceil}{s O{} m}{%
\IfBooleanTF{#1} % starred
{\left\lceil#3\right\rceil} % \ceil*[..]{..}
{#2\lceil#3#2\rceil} % \ceil[..]{..}
}
\begin{document}
\[\ceil[\big]{x} \quad \ceil[\Big]{x} \quad \ceil[\bigg]{x} \quad \ceil[\Bigg]{x} \quad \ceil*[\big]{\frac{1}{2}}\]
\end{document}
The optional argument is ignored in the starred version of \ceil*[..]{..}.
-
4You could eliminate the
\IfNoValueTF {\lceil#3\rceil}if you used{s O{} m}. Then the second arg#2will be defined so only need#2\lceil#3#2\rceil. – Peter Grill Jan 25 '12 at 18:29
\lceiland\rceilare the appropriate markups. – Hugh Perkins Aug 21 '17 at 8:15