如何将“\delta”格式化为**粗体倾斜无衬线字体**

Question

我如何格式化\delta为粗体斜体无衬线字体. 期刊指南要求粗体斜体无衬线字体宏定义的\mathsfbi应该用于张量和矩阵，例如\mathsfbi{E}。显然，它适合普通字母。但是当我使用 时\mathsfbi{\delta}，结果似乎没有任何变化。我的问题是如何将它应用于希腊字母？

Answer 1

您可以使用提供的字体newtxsf（或另一个提供无衬线数学的字体）：

\documentclass{article}
\usepackage{lmodern,pdftexcmds,amsmath}

\DeclareMathAlphabet{\mathsfbi}{OT1}{\sfdefault}{bx}{sl}
\DeclareMathVersion{sfletters}
\SetSymbolFont{letters}{sfletters}{OML}{ntxsfmi}{b}{it}

\makeatletter
\newcommand{\mathbfsbilow}[1]{%
  \text{\mathversion{sfletters}$\m@th#1$}%
}

\DeclareRobustCommand{\tensor}[1]{%
  \begingroup
  \ifcat\noexpand #1\relax
    % assume Greek letter
    \edef\greek@test{\detokenize{#1}}%
    \edef\greek@test{\expandafter\@cdr\greek@test\@nil}%
    \edef\greek@test{\expandafter\@car\greek@test\@nil}%
    \edef\x{\the\lccode\expandafter`\greek@test}%
    \edef\y{\number\expandafter`\greek@test}%
    \ifnum\x=\y\relax
      % the command name starts with a lowercase letter
      \mathbfsbilow{#1}%
    \else
      \mathsfbi{#1}%
    \fi
  \else
    \mathsfbi{#1}%
  \fi
  \endgroup
}
\makeatother

\begin{document}

$\tensor{T}+\tensor{\Gamma}+\tensor{\delta}$

$\tensor{\alpha}\tensor{\beta}\tensor{\gamma}$

\end{document}