答案1
我的答案在此有所变化:不同的和符号
\documentclass{article}
\usepackage{mathtools,txfonts}
% =============================================
%Import symbols from font cmex without importing the whole package
% =============================================
\DeclareFontFamily{U} {cmex}{}
\DeclareFontShape{U}{cmex}{m}{n}{
<-6> cmex5
<6-7> cmex6
<7-8> cmex7
<8-9> cmex8
<9-10> cmex9
<10-12> cmex10
<12-> cmex12}{}
\DeclareSymbolFont{Xcmex} {U} {cmex}{m}{n}
\DeclareMathSymbol{\Xdprod}{\mathop}{Xcmex}{89}
\DeclareMathSymbol{\Xtprod}{\mathop}{Xcmex}{81}
\DeclareMathOperator*{\Xprod}{\mathchoice{\Xdprod}{\Xtprod}{\Xtprod}{\Xtprod}}
% =============================================
%\usepackage{fonttable}
\begin{document}
\centering
prod under txfonts:\par
$\prod_{i=1}^2 x_i $
\[\prod_{i=1}^2 x_i \]
Defined Xprod from cmex:\par
$\Xprod_{i=1}^2 x_i $
\[\Xprod_{i=1}^2 x_i \]
%\tiny\fonttable{cmex8}
\end{document}
答案2
在现代工具链中,unicode-math
你可以这样写:
\usepackage{unicode-math}
%% There is also a TeX Gyre Termes X that’s a more exact clone of
%% newtxtext, or any Times font would work here:
\setmainfont{TeX Gyre Termes}
\setmathfont{TeX Gyre Termes Math}
\setmathfont[range=\prod, Scale=MatchUppercase]{Latin Modern Math}