电子书中的排版数学¶

Calibre电子书阅读器能够显示嵌入在电子书(EPUB和HTML文件)中的数学。您可以直接使用TeX、MathML或AsciiMath来排版数学。Calibre电子书阅读器使用优秀的`MathJax<https://www.mathjax.org>`_书库来实现这一点。这是一个简短的教程，介绍如何使用数学制作电子书，并与优秀的电子书阅读器配合使用。

带有数学公式的简单 HTML 文件¶

你可以直接在简单 HTML 文件中的段落里穿插数学公式，这样 calibre 电子书阅读器就能正确排版数学公式。在如下的例子中，我们用 TeX 的数学公式记法。如你所见，你可以使用通常的 TeX 命令，不过要注意把 & 和大于小于符号分别写成 & < 和 >。

第一步是告诉calibre这将包含数学。您可以通过将以下代码片段添加到<head> HTML文件的章节来完成此操作：

<script type="text/x-mathjax-config"></script>

就是这样，现在你可以像在 .tex 文件中一样书写数学公式。例如，下列是洛伦茨方程:

<h2>The Lorenz Equations</h2>

<p>
\begin{align}
\dot{x} &amp; = \sigma(y-x) \\
\dot{y} &amp; = \rho x - y - xz \\
\dot{z} &amp; = -\beta z + xy
\end{align}
</p>

这段代码在 calibre 电子书阅读器看起来像如下的截图这样。

完整的 HTML 文件，附带更多的方程式和行内数学公式在下面列出。你可以将此 HTML 文件在 calibre 中转成 EPUB，这样就能得到一本可以轻而易举与他人分享的电子书。

这是生成的 EPUB 文件： mathjax.epub

<!DOCTYPE html>
<html>
<!-- Copyright (c) 2012 Design Science, Inc. -->
<head>
<title>Math Test Page</title>
<meta http-equiv="content-type" content="text/html; charset=UTF-8" />

<!-- This script tag is needed to make calibre's ebook-viewer recpgnize that this file needs math typesetting -->
<script type="text/x-mathjax-config">
    // This line adds numbers to all equations automatically, unless explicitly suppressed.
    MathJax.tex = {tags: 'all'};
</script>

<style>
h1 {text-align:center}
h2 {
  font-weight: bold;
  background-color: #DDDDDD;
  padding: .2em .5em;
  margin-top: 1.5em;
  border-top: 3px solid #666666;
  border-bottom: 2px solid #999999;
}
</style>
</head>
<body>

<h1>Sample Equations</h1>

<h2>The Lorenz Equations</h2>

<p>
\begin{align}
\dot{x} &amp; = \sigma(y-x) \label{lorenz}\\
\dot{y} &amp; = \rho x - y - xz \\
\dot{z} &amp; = -\beta z + xy
\end{align}
</p>

<h2>The Cauchy-Schwarz Inequality</h2>

<p>\[
\left( \sum_{k=1}^n a_k b_k \right)^{\!\!2} \leq
 \left( \sum_{k=1}^n a_k^2 \right) \left( \sum_{k=1}^n b_k^2 \right)
\]</p>

<h2>A Cross Product Formula</h2>

<p>\[
  \mathbf{V}_1 \times \mathbf{V}_2 =
   \begin{vmatrix}
    \mathbf{i} &amp; \mathbf{j} &amp; \mathbf{k} \\
    \frac{\partial X}{\partial u} &amp; \frac{\partial Y}{\partial u} &amp; 0 \\
    \frac{\partial X}{\partial v} &amp; \frac{\partial Y}{\partial v} &amp; 0 \\
   \end{vmatrix}
\]</p>

<h2>The probability of getting \(k\) heads when flipping \(n\) coins is:</h2>

<p>\[P(E) = {n \choose k} p^k (1-p)^{ n-k} \]</p>

<h2>An Identity of Ramanujan</h2>

<p>\[
   \frac{1}{(\sqrt{\phi \sqrt{5}}-\phi) e^{\frac25 \pi}} =
     1+\frac{e^{-2\pi}} {1+\frac{e^{-4\pi}} {1+\frac{e^{-6\pi}}
      {1+\frac{e^{-8\pi}} {1+\ldots} } } }
\]</p>

<h2>A Rogers-Ramanujan Identity</h2>

<p>\[
  1 +  \frac{q^2}{(1-q)}+\frac{q^6}{(1-q)(1-q^2)}+\cdots =
    \prod_{j=0}^{\infty}\frac{1}{(1-q^{5j+2})(1-q^{5j+3})},
     \quad\quad \text{for $|q|&lt;1$}.
\]</p>

<h2>Maxwell's Equations</h2>

<p>
\begin{align}
  \nabla \times \vec{\mathbf{B}} -\, \frac1c\, \frac{\partial\vec{\mathbf{E}}}{\partial t} &amp; = \frac{4\pi}{c}\vec{\mathbf{j}} \\
  \nabla \cdot \vec{\mathbf{E}} &amp; = 4 \pi \rho \\
  \nabla \times \vec{\mathbf{E}}\, +\, \frac1c\, \frac{\partial\vec{\mathbf{B}}}{\partial t} &amp; = \vec{\mathbf{0}} \\
  \nabla \cdot \vec{\mathbf{B}} &amp; = 0
\end{align}
</p>

<h2>Inline Mathematics</h2>

<p>While display equations look good for a page of samples, the
ability to mix math and text in a paragraph is also important.  This
expression \(\sqrt{3x-1}+(1+x)^2\) is an example of an inline equation.  As
you see, equations can be used this way as well, without unduly
disturbing the spacing between lines.</p>

<h2>References to equations</h2>

<p>Here is a reference to the Lorenz Equations (\ref{lorenz}). Clicking on the equation number will take you back to the equation.</p>

</body>
</html>

备注

The calibre E-book viewer supports MathML as well as TeX, but you must include the <script type="text/x-mathjax-config"></script> line in your HTML file otherwise the MathML will not render.

Related Topics

电子书中的排版数学¶

带有数学公式的简单 HTML 文件¶

更多信息¶