如何将 Computer Modern lambda 与 newtxmath 包一起使用？

Question

我尝试\lambda在文档中使用 CMU，因为我更喜欢它的外观，而不是newtxmath。我对 也有类似的看法\sum，但我找到了一个邮政替换总和符号。我尝试查看字体表，但无法理解，即使查阅了文档也是如此。我只是不确定 lambda 的代码是什么；似乎“50 是 \sum。下面是 MWE。

\documentclass[11pt,a4paper]{article}
\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts,theorem}
\usepackage{amssymb}
\usepackage{newtxtext}
\usepackage{newtxmath}
\usepackage{fonttable}

\DeclareSymbolFont{cmlargesymbols}{OMX}{cmex}{m}{n}
\DeclareSymbolFont{mdsymbols}     {OMS}{mdput}{m}{n}
\DeclareSymbolFont{mdlargesymbols}{OMX}{mdput}{m}{n}

\DeclareMathDelimiter{\lbrace}{\mathopen}{mdsymbols}{"66}{mdlargesymbols}{"08}
\DeclareMathDelimiter{\rbrace}{\mathclose}{mdsymbols}{"67}{mdlargesymbols}{"09}
\DeclareMathSymbol{\braceld}{\mathord}{mdlargesymbols}{"7A}
\DeclareMathSymbol{\bracerd}{\mathord}{mdlargesymbols}{"7B}
\DeclareMathSymbol{\bracelu}{\mathord}{mdlargesymbols}{"7C}
\DeclareMathSymbol{\braceru}{\mathord}{mdlargesymbols}{"7D}

\let\sum\relax
\DeclareMathSymbol{\sum}{\mathop}{cmlargesymbols}{"50}

% \let\lambda\relax
% \DeclareMathSymbol{\lambda}{\mathop}{cmlargesymbols}{???}

\makeatletter
\def\downbracefill{$\m@th \setbox\z@\hbox{$\braceld$}%
  \braceld\leaders\vrule \@height\ht\z@ \@depth\z@\hfill\braceru
  \bracelu\leaders\vrule \@height\ht\z@ \@depth\z@\hfill\bracerd$}
\def\upbracefill{$\m@th \setbox\z@\hbox{$\braceld$}%
  \bracelu\leaders\vrule \@height\ht\z@ \@depth\z@\hfill\bracerd
  \braceld\leaders\vrule \@height\ht\z@ \@depth\z@\hfill\braceru$}
\makeatother

\let\textbraceleft\relax \let\textbraceright\relax
\DeclareRobustCommand{\textbraceleft}{%
  {\fontfamily{mdput}\fontencoding{OMS}\selectfont\char"66}}
\DeclareRobustCommand{\textbraceright}{%
  {\fontfamily{mdput}\fontencoding{OMS}\selectfont\char"67}}



\begin{document}
\fonttable{cmr12}
\Huge
\[
\sum_{n=1}^{\infty} \int_{-\infty}^{\infty} \lambda
\]
\end{document}

Answer 1

\documentclass{article}
\pagestyle{empty}
\usepackage{newtxtext}
\usepackage{newtxmath}
\usepackage{amsmath}
\DeclareSymbolFont{cmlargesymbols}{OMX}{cmex}{m}{n}
\let\sum\relax
\DeclareMathSymbol{\sum}{\mathop}{cmlargesymbols}{"50}
\DeclareSymbolFont{cmletters}{OML}{cmm}{m}{it}
\SetSymbolFont{cmletters}{bold}{OML}{cmm}{b}{it}
\DeclareSymbolFontAlphabet{\mathnormal}{cmletters}
\DeclareMathSymbol{\lambda}{\mathord}{cmletters}{"15}
\begin{document}
\begin{equation*}
\sum_{n=1}^{\infty} \int_{-\infty}^{\infty} \lambda
\end{equation*}
\end{document}