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bookdown Authoring Books and Technical Documents with R Markdown

Yihui Xie

Section 2.1 Markdown syntax

In this section, we give a very brief introduction to Pandoc’s Markdown. Readers who are familiar with Markdown can skip this section. The comprehensive syntax of Pandoc’s Markdown can be found on the Pandoc website pandoc.org.
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Subsection 2.1.1 Inline formatting

You can make text italic by surrounding it with underscores or asterisks, e.g., _text_ or *text*. For bold text, use two underscores (__text__) or asterisks (**text**). Text surrounded by ~ will be converted to a subscript (e.g., H~2~SO~4~), and similarly, two carets (^) produce a superscript (e.g., Fe^2+^). To mark text as inline code, use a pair of backticks, e.g., `code`
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To include literal backticks, use more backticks outside, e.g., you can use two backticks to preserve one backtick inside: `` `code` ``.
. Small caps can be produced by the HTML tag span, e.g., <span style="font-variant:small-caps;">Small Caps</span>. Links are created using [text](link), e.g., [Posit](https://www.posit.co), and the syntax for images is similar: just add an exclamation mark, e.g., ![alt text or image title](path/to/image). Footnotes are put inside the square brackets after a caret ^[], e.g., ^[This is a footnote.]. We will talk about citations in Section 2.8.
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Subsection 2.1.2 Block-level elements

Section headers can be written after a number of pound signs, for example,
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# First-level header

## Second-level header

### Third-level header
If you do not want a certain heading to be numbered, you can add {-} after the heading.
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# Preface {-}
Unordered list items start with *, -, or +, and you can nest one list within another list by indenting the sub-list by four spaces.
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- one item
- one item
- one item
    - one item
    - one item
The output is:
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Ordered list items start with numbers (the rule for nested lists is the same as above).
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1. the first item
2. the second item
3. the third item
The output does not look too much different with the Markdown source:
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  1. the first item
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  2. the second item
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  3. the third item
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Blockquotes are written after >, e.g.,
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> "I thoroughly disapprove of duels. If a man should challenge me,
  I would take him kindly and forgivingly by the hand and lead him
  to a quiet place and kill him."
>
> --- Mark Twain
"I thoroughly disapprove of duels. If a man should challenge me, I would take him kindly and forgivingly by the hand and lead him to a quiet place and kill him."
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— Mark Twain
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Plain code blocks can be written after three or more backticks, and you can also indent the blocks by four spaces.
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```
This text is displayed verbatim / preformatted
```

Or indent by four spaces:

    This text is displayed verbatim / preformatted
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Subsection 2.1.3 Math expressions

Inline LaTeX equations can be written in a pair of dollar signs using the LaTeX syntax, e.g., $f(k) = {n \choose k} p^{k} (1-p)^{n-k}$ (actual output: \(f(k) = \binom{n}{k} p^{k} (1-p)^{n-k}\)); math expressions of the display style can be written in a pair of double dollar signs, e.g., $$f(k) = {n \choose k} p^{k} (1-p)^{n-k}$$, and the output looks like this:
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\begin{equation*} f(k) = \binom{n}{k} p^{k} (1-p)^{n-k} \end{equation*}
You can also use math environments inside $ $ or $$ $$, e.g.,
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$$\begin{array}{ccc}
x_{11} & x_{12} & x_{13}\\
x_{21} & x_{22} & x_{23}
\end{array}$$
\begin{equation*} \begin{array}{ccc} x_{11} \amp x_{12} \amp x_{13}\\ x_{21} \amp x_{22} \amp x_{23} \end{array} \end{equation*} 
$$X = \begin{bmatrix}1 & x_{1}\\
1 & x_{2}\\
1 & x_{3}
\end{bmatrix}$$
\begin{equation*} X = \begin{bmatrix} 1 \amp x_{1}\\ 1 \amp x_{2}\\ 1 \amp x_{3} \end{bmatrix} \end{equation*} 
$$\Theta = \begin{pmatrix}\alpha & \beta\\
\gamma & \delta
\end{pmatrix}$$
\begin{equation*} \Theta = \begin{pmatrix} \alpha \amp \beta\\ \gamma \amp \delta \end{pmatrix} \end{equation*} 
$$\begin{vmatrix}a & b\\
c & d
\end{vmatrix}=ad-bc$$
\begin{equation*} \begin{vmatrix} a \amp b\\ c \amp d \end{vmatrix} = ad - bc \end{equation*}
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