答案1
您可以将符号降低相对于 的多余高度<
。但是您不应该这样做。
\documentclass{article}
\usepackage{amsmath,amssymb}
\let\originallesssim\lesssim
\let\originalgtrsim\gtrsim
\DeclareRobustCommand{\lesssim}{%
\mathrel{\mathpalette\lowersim\originallesssim}%
}
\DeclareRobustCommand{\gtrsim}{%
\mathrel{\mathpalette\lowersim\originalgtrsim}%
}
\makeatletter
\newcommand{\lowersim}[2]{%
\sbox\z@{$#1<$}%
\raisebox{-\dimexpr\height-\ht\z@}{$\m@th#1#2$}%
}
\makeatother
\begin{document}
$A<B\lesssim C\gtrsim D$
$\scriptstyle A<B\lesssim C\gtrsim D$
\end{document}
答案2
您可以\vtop
在\halign
其中使用:
\newcount\mstylenum
\def\varstyle#1{\mathchoice{\mstylenum=0 #1}{\mstylenum=1 #1}{\mstylenum=2 #1}{\mstylenum=3 #1}}
\def\usestyle{\ifcase\mstylenum \displaystyle\or\textstyle\or\scriptstyle\or\scriptscriptstyle\fi}
\def\gensim#1{\mathrel{\varstyle{\vtop{\offinterlineskip
\halign{\hfil$\usestyle##$\hfil\cr#1\cr\noalign{\kern1pt}\sim\cr}}}}}
\def\lessim{\gensim<} \def\grtsim{\gensim>}
$a < b \lessim c \grtsim d, \scriptstyle a < b \lessim c$
\bye