I use $\Diamond$ as a product sign and want to have something like $\bigDiamond_{i=1}^{n}$ to note multiple $\Diamond$-products. Similar to $\wedge$ and $\bigwedge$ or $\vee$ and $\bigvee$. Is there a package for this problem?
[Tex/LaTex] sign for multiple $\Diamond$-product
math-modemath-operators
Related Solutions
With amssymb you have \blacklozenge:
\documentclass{article}
\usepackage{amssymb,graphicx}
\newcommand{\bDiamond}{\mathbin{\Diamond}}
\newcommand{\bLozenge}{\mathbin{\blacklozenge}}
\makeatletter
\newcommand\bigDiamond{\mathop{\mathpalette\bigDi@mond\relax}}
\newcommand\bigDi@mond[2]{%
\vcenter{\hbox{\m@th
\scalebox{\ifx#1\displaystyle 2\else1.2\fi}{$#1\Diamond$}%
}}%
}
\newcommand\bigLozenge{\mathop{\mathpalette\bigL@zenge\relax}}
\newcommand\bigL@zenge[2]{%
\vcenter{\hbox{\m@th
\scalebox{\ifx#1\displaystyle 2\else1.2\fi}{$#1\blacklozenge$}%
}}%
}
\makeatother
\begin{document}
\[
\bigoplus_{i=1}^n % just for comparison
\bigDiamond_{i=1}^n (a_i\bDiamond b_i)\quad
\textstyle\bigDiamond_{i=1}^n a_i\quad
\scriptstyle\bigDiamond_{i=1}^n a_i\quad
\scriptscriptstyle\bigDiamond_{i=1}^n a_i
\]
\[
\bigoplus_{i=1}^n % just for comparison
\bigLozenge_{i=1}^n (a_i\bLozenge b_i)\quad
\textstyle\bigLozenge_{i=1}^n a_i\quad
\scriptstyle\bigLozenge_{i=1}^n a_i\quad
\scriptscriptstyle\bigLozenge_{i=1}^n a_i
\]
\end{document}
You mention that a regular upper-case \Lambda won't cut it, but you could use a sans-serif one. I took the liberty of adapting @egreg's answer to this question:
\documentclass{article}
\usepackage[math-style=ISO]{unicode-math}
\defaultfontfeatures{Scale=MatchUppercase}
\setmathfontface\mathsans{TeX Gyre Heros}
\newcommand{\wedgeprod}{\mathsans{\mupLambda}}
\begin{document}
$$\wedgeprod^k V = {} \underbrace{ V \wedge V \dots \wedge V }_{\text{$k$ times}}$$
\end{document}
This produces:
Definitely far from perfect, but better than nothing.
Best Answer
For such a simple geometric symbol, scaling it seems the easiest road. You might want a larger factor than 1.2 for text style, adjust at will. However, 2 is the right scaling factor for display style.
Don't use
\Diamondfor a binary operation or the spacing would be wrong; you need to use\mathbin{\Diamond}, which is what\bDiamonddoes.