我想寻求帮助，弄清楚究竟是什么引发了有关使用某些字体渲染文本样式分数的奇怪现象韋斯維爾（版本 2.6.3，作为 Arch Linux 上 texlive-bin 2019.51075-3 包的一部分分发）。
（我在玩动画库时偶然发现了这一点马尼姆，它通过在 LaTeX 中运行公式，然后使用 dvisvgm 将 dvi 转换为 svg 来呈现公式。）
这是一个非常简单的例子，造成了麻烦，svg测试.tex：
\documentclass[preview]{standalone}
\usepackage{fourier}
\begin{document}
$y = \sin \frac{1}{x}$
\end{document}
处理这个
latex svgtest.tex; dvisvgm svgtest.dvi -n -o svgtest.svg
生成以下文件，svg测试.svg：
<?xml version='1.0' encoding='UTF-8'?>
<!-- This file was generated by dvisvgm 2.6.3 -->
<svg version='1.1' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' width='33.871205pt' height='12.091864pt' viewBox='0.498134 -8.571499 33.871205 12.091864'>
<defs>
<path id='g3-49' d='M3.990416 0V-0.26481L3.22338 -0.32873C3.03162 -0.346993 2.922044 -0.420044 2.922044 -0.776168V-6.154555L2.876387 -6.209343L0.995321 -5.889745V-5.66146L1.84454 -5.561015C1.999774 -5.542752 2.063693 -5.469701 2.063693 -5.204891V-0.776168C2.063693 -0.602672 2.036299 -0.493095 1.981511 -0.429175C1.935854 -0.365255 1.862803 -0.337861 1.762358 -0.32873L0.995321 -0.26481V0H3.990416Z'/>
<path id='g1-198' d='M5.798431 -1.305788V-1.835409H0.776168V-1.305788H5.798431ZM5.798431 -3.314693V-3.844314H0.776168V-3.314693H5.798431Z'/>
<path id='g8-120' d='M3.518509 -0.957701C3.351952 -0.645407 3.164576 -0.277594 2.97026 -0.277594C2.838403 -0.277594 2.782884 -0.437211 2.630207 -1.054859L2.408131 -1.96398C2.657966 -2.408131 3.011899 -2.96332 3.213155 -2.96332C3.275614 -2.96332 3.331133 -2.94944 3.407471 -2.907801C3.47687 -2.880042 3.546268 -2.852282 3.629547 -2.852282C3.782224 -2.852282 3.927961 -2.998019 3.927961 -3.185396C3.927961 -3.400531 3.768344 -3.48381 3.574028 -3.48381C3.206215 -3.48381 2.893921 -3.150696 2.651026 -2.762064L2.345673 -2.290154H2.331793L2.054198 -3.45605L2.012559 -3.48381L0.867482 -3.136817L0.888302 -2.97026L1.408792 -3.004959C1.533709 -3.011899 1.582288 -2.9772 1.658626 -2.657966L1.908461 -1.651687L1.714145 -1.318573C1.415731 -0.811964 1.158957 -0.451091 0.9924 -0.451091C0.923001 -0.451091 0.853603 -0.47885 0.791144 -0.51355C0.721745 -0.548249 0.631527 -0.617648 0.51355 -0.617648C0.333113 -0.617648 0.215136 -0.437211 0.215136 -0.270655C0.215136 -0.069399 0.381692 0.083278 0.659287 0.083278C1.131197 0.083278 1.401852 -0.388632 1.686386 -0.853603L1.96398 -1.311633H1.97786L2.102777 -0.770324C2.234635 -0.215136 2.366492 0.083278 2.720425 0.083278C3.227035 0.083278 3.490749 -0.437211 3.698945 -0.860543L3.518509 -0.957701Z'/>
<use id='g13-121' xlink:href='#g8-121' transform='scale(1.315788)'/>
<use id='g18-105' xlink:href='#g3-105'/>
<use id='g18-110' xlink:href='#g3-110'/>
<use id='g18-115' xlink:href='#g3-115'/>
<use id='g15-49' xlink:href='#g3-49' transform='scale(0.760001)'/>
</defs>
<g id='page1'>
<use x='0.498134' y='0' xlink:href='#g13-121'/>
<use x='7.333545' y='0' xlink:href='#g1-198'/>
<use x='15.633477' y='0' xlink:href='#g18-115'/>
<use x='19.628496' y='0' xlink:href='#g18-105'/>
<use x='22.29848' y='0' xlink:href='#g18-110'/>
<use x='30.405611' y='-3.925267' xlink:href='#g15-49'/>
<rect x='30.136829' y='-2.846123' height='0.531591' width='4.232511'/>
<use x='30.288264' y='3.437093' xlink:href='#g8-120'/>
</g>
</svg>
在我测试过的每个程序（Firefox、Inkscape、Emacs）中，此 svg 的呈现方式如下：
查看 svg 代码，例如，我们看到“page1”组中的第一个 <use> 标签（应该是“y”字符）引用元素 g13-121，而前几行引用元素 g8-121，该元素未在任何地方定义，因此毫不奇怪图片中只有空格而不是“y”。
将此与使用默认 Computer Modern 字体的相同示例进行对比，其工作方式符合预期：
\documentclass[preview]{standalone}
\begin{document}
$y = \sin \frac{1}{x}$
\end{document}
latex svgtest.tex; dvisvgm svgtest.dvi -n -o svgtest.svg
<?xml version='1.0' encoding='UTF-8'?>
<!-- This file was generated by dvisvgm 2.6.3 -->
<svg version='1.1' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' width='38.131002pt' height='11.852377pt' viewBox='0 -8.416865 38.131002 11.852377'>
<defs>
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<g id='page1'>
<use x='0' y='0' xlink:href='#g0-121'/>
<use x='8.009276' y='0' xlink:href='#g2-61'/>
<use x='18.525356' y='0' xlink:href='#g2-115'/>
<use x='22.455073' y='0' xlink:href='#g2-105'/>
<use x='25.222482' y='0' xlink:href='#g2-110'/>
<use x='33.886483' y='-3.922607' xlink:href='#g3-49'/>
<rect x='33.613201' y='-2.68991' height='0.398484' width='4.517787'/>
<use x='33.613201' y='3.435512' xlink:href='#g1-120'/>
</g>
</svg>
但接下来才是真正奇怪的部分。回到傅里叶字体，以下所有公式做按预期工作（一次一个，但为了简单起见，我在这里将它们全部放在一个示例中）：
\documentclass[preview]{standalone}
\usepackage{fourier}
\begin{document}
$$y = \sin \frac{1}{x}$$
$y = \frac{1}{x}$
$y = \sin \frac{z}{x}$
$y = \sin \left( \frac{1}{x} \right)$
\end{document}
但是这个不起作用（结果看起来很像上面的第一个例子）：
\documentclass[preview]{standalone}
\usepackage{fourier}
\begin{document}
$y = \sin ( \frac{1}{x} )$
\end{document}
和
\usepackage{mathpazo}
结果与 Fourier 相同。另一方面，
\usepackage{newtxmath}
一切都按预期运行，就像 Computer Modern 一样。
所有 dvi 文件都可以用 xdvi、dvips、dvipng 等格式显示，但显然 dvi 文件中有一些
$y = \sin \frac{1}{x}$
和
$y = \sin ( \frac{1}{x} )$
使用 fourier 和 mathpazo 包，它与其他所有示例都不同，从而触发了 dvisvgm 中的这种奇怪行为（错误？）。由于 dvi 是二进制格式，我无法准确解释这个神秘属性是什么，但也许一些 TeX 专家可以提供帮助？
答案1
经过进一步调查，我终于找到了字符缺失的原因。与我在评论中提到的相反，我现在能够使用 dvisvgm 2.6.3 重现该问题，并且可以对变更集进行二分。这实际上是 dvisvgm 中的一个错误，已经已报告但直到现在，这种情况才偶尔发生，并且只出现在多页 DVI 文件中。几个月前我在 2.7.3 版本中修复了这个问题。因此，遗憾的是，除了等待更新的版本，您无能为力。