I'm trying to get a big cross which I can subscript in order to denote a generalized cartesian product (much like how \bigcup
works for generalized unions). How can I accomplish this?
6 Answers
Looking in the The Comprehensive LaTeX Symbol List reveals a \bigtimes
symbol defined by the mathabx
package.
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6I just found out (accidentally :)) that the
\bigtimes
symbol is also defined in the mathtools package. Commented Sep 12, 2011 at 13:45 -
12regarding
mathabx
beware that it changes the shape of many other symbols; it is recommended to extract the code for just the desired symbol(s) into your preamble to avoid unexpected results. Commented Sep 12, 2011 at 13:57
If you don't mind using a different font, kpfonts
gives you the \varprod
command:
\documentclass{article}
\usepackage{kpfonts}
\begin{document}
$\varprod_{i=1}^n A_i$
\[
\varprod_{i=1}^n A_i
\]
\end{document}
I would be more inclined to use \prod
to denote a generalised cartesian product, though.
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1Strictly speaking, \prod should be the general symbol for product in categorical sense. The Cartesian product is a product in many categories such as sets and modules, but it is not always the case.– ashpoolCommented May 4, 2014 at 18:44
I am sure others will come up with simpler solutions, but here is an overkill solution that might be useful:
\documentclass{article}
\usepackage{amsmath}
\usepackage{tikz}
\newcommand{\Cross}{\mathbin{\tikz [x=1.4ex,y=1.4ex,line width=.2ex] \draw (0,0) -- (1,1) (0,1) -- (1,0);}}%
\begin{document}
$A \Cross B$
\end{document}
Adjust the x=
and y=
options to change the size, and the line width=
to adjust the thickness of the line. The \mathbin
ensures that correct spacing for a binary operator is placed around the symbol.
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1If you are down voting, it would be helpful it your provided some explanation so others can know what is wrong with this solution, or why you are opposed to this solution. Commented Feb 19, 2013 at 19:41
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I'm not the downvoter, but you seem to be re-implementing the binary cartesian product symbol, and the OP is asking about a "sigma-style" symbol to apply to the Cartesian product of a family of sets. Commented Mar 27, 2013 at 0:29
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Still, I wouldn't have downvoted. I got to this answer from your comments on tex.stackexchange.com/questions/104164/… and I agree with your POV. Commented Mar 27, 2013 at 1:17
There is a simple command for that in the mathabx
package:
\documentclass{minimal}
\usepackage{mathabx}
\begin{document}
$\bigtimes\limits_{x=1}$
\end{document}
In fact if you find another operator symbol you fancy, you can try the \limits
command on it. It may actually work. :)
I hope this answers it. :)
If you can use unicode-math
, the symbol you are looking for is at U+2A09 'N-ARY TIMES OPERATOR'
\usepackage{unicode-math}
\begin{equation}
B ⊂ ⨉_{x∈J}A(x)
\end{equation}
This package only works on the XeLaTex and LuaLaTeX engines though.
Might I suggest a very simple-minded approach?
Why not just use the letter "X"? Below, I inserted \sf
to render the symbol more distinguishable
$${\sf X}^n_{i=1} A_i = A_1\times \cdots \times A_n$$
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1Please read the following posts: Does it matter if I use
\textit
or\it
,\bfseries
or\bf
, etc., Will two-letter font style commands (\bf
,\it
, …) ever be resurrected in LaTeX?, Why is\[
…\]
preferable to$$
?– Werner ♦Commented Jan 29, 2013 at 3:48
\bigotimes
without the 'O' maybe?\prod
for n-ary Cartesian products, not a giant\times
?