pseudocode.js is a JavaScript library that typesets pseudocode beautifully to HTML.
- Intuitive grammar: Pseudocode.js takes a LaTeX-style input that supports the algorithmic constructs from LaTeX's algorithm packages. With or without LaTeX experience, a user should find the grammar fairly intuitive.
- Print quality: The HTML output produced by pseudocode.js is (almost) identical with the pretty algorithms printed on publications that are typeset by LaTeX.
- Math formula support: Inserting math formulas in pseudocode.js is as easy
as LaTeX. Just enclose math expression in
$...$
or\(...\)
.
It supports all modern browsers, including Chrome, Safari, Firefox, Edge, and Edge.
Visit the project website for a demo.
pseudocode.js can render math formulas using either KaTeX, or MathJax.
Include the following in the <head>
of your page:
<script src="https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.16.7/katex.min.js"
integrity="sha512-EKW5YvKU3hpyyOcN6jQnAxO/L8gts+YdYV6Yymtl8pk9YlYFtqJgihORuRoBXK8/cOIlappdU6Ms8KdK6yBCgA=="
crossorigin="anonymous" referrerpolicy="no-referrer">
</script>
Include the following in the <head>
of your page:
<script src="https://cdn.jsdelivr.net/npm/[email protected]/MathJax.js?config=TeX-AMS_CHTML-full"
integrity="sha256-DViIOMYdwlM/axqoGDPeUyf0urLoHMN4QACBKyB58Uw="
crossorigin="anonymous" referrerpolicy="no-referrer">
</script>
<script type="text/x-mathjax-config">
MathJax.Hub.Config({
tex2jax: {
inlineMath: [['$','$'], ['\\(','\\)']],
displayMath: [['$$','$$'], ['\\[','\\]']],
processEscapes: true,
processEnvironments: true,
}
});
</script>
Note The
-full
configuration is larger and loads more extensions, but I recommend using it it just to avoid any hiccups later. You may want to use the standard configuration instead if you do not require additional packages.
Include the following in the <head>
of your page:
<script>
MathJax = {
tex: {
inlineMath: [['$','$'], ['\\(','\\)']],
displayMath: [['$$','$$'], ['\\[','\\]']],
processEscapes: true,
processEnvironments: true,
}
}
</script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/es5/tex-chtml-full.js"
integrity="sha256-kbAFUDxdHwlYv01zraGjvjNZayxKtdoiJ38bDTFJtaQ="
crossorigin="anonymous">
</script>
Note The
-full
configuration is larger and loads more extensions, but I recommend using it it just to avoid any hiccups later. You may want to use the standard configuration instead if you do not require additional packages, such ascolor
.
Include the following in the <head>
of your page:
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/[email protected]/build/pseudocode.min.css">
<script src="https://cdn.jsdelivr.net/npm/[email protected]/build/pseudocode.min.js">
</script>
You may also use the latest
tag for pseudocode instead,
but jsDelivr might be delayed in updating the pointer for this tag.
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/pseudocode@latest/build/pseudocode.min.css">
<script src="https://cdn.jsdelivr.net/npm/pseudocode@latest/build/pseudocode.min.js">
</script>
We assume the pseudocode to be rendered is in a <pre>
DOM element.
Here is an example that illustrates a quicksort algorithm:
<pre id="quicksort" class="pseudocode">
% This quicksort algorithm is extracted from Chapter 7, Introduction to Algorithms (3rd edition)
\begin{algorithm}
\caption{Quicksort}
\begin{algorithmic}
\PROCEDURE{Quicksort}{$A, p, r$}
\IF{$p < r$}
\STATE $q = $ \CALL{Partition}{$A, p, r$}
\STATE \CALL{Quicksort}{$A, p, q - 1$}
\STATE \CALL{Quicksort}{$A, q + 1, r$}
\ENDIF
\ENDPROCEDURE
\PROCEDURE{Partition}{$A, p, r$}
\STATE $x = A[r]$
\STATE $i = p - 1$
\FOR{$j = p$ \TO $r - 1$}
\IF{$A[j] < x$}
\STATE $i = i + 1$
\STATE exchange
$A[i]$ with $A[j]$
\ENDIF
\STATE exchange $A[i]$ with $A[r]$
\ENDFOR
\ENDPROCEDURE
\end{algorithmic}
\end{algorithm}
</pre>
Insert the following Javascript snippet at the end of your document:
<script>
pseudocode.renderElement(document.getElementById("quicksort"));
</script>
Insert the following Javascript snippet at the end of your document:
<script>
pseudocode.renderClass("pseudocode");
</script>
There are several packages for typesetting algorithms in LaTeX, among which
algorithmic
package is the most simple and intuitive, and is chosen by IEEE in its
LaTeX template file.
The grammar of pseudocode.js is mostly compatible with algorithmic
package with
a few improvement to make it even more easier to use.
Commands for typesetting algorithms must be enclosed in an algorithmic
environment:
\begin{algorithmic}
# A precondition is optional
\REQUIRE <text>
# A postcondition is optional
\ENSURE <text>
# An input is optional
\INPUT <text>
# An output is optional
\OUTPUT <text>
# The body of your code is a <block>
\STATE ...
\end{algorithmic}
<block>
can include zero or more <statement>
, <control>
, <comment>
and <function>
:
# A <statement> can be:
\STATE <text>
\RETURN <text>
\PRINT <text>
# A <control> can be:
# A conditional
\IF{<condition>}
<block>
\ELIF{<condition>}
<block>
\ELSE
<block>
\ENDIF
# Or a loop: \WHILE, \FOR or \FORALL
\WHILE{<condition>}
<block>
\ENDWHILE
# Or a repeat: \REPEAT <block> \UNTIL{<cond>}
\REPEAT
<block>
\UNTIL{<cond>}
# A <function> can by defined by either \FUNCTION or \PROCEDURE
# Both are exactly the same
\FUNCTION{<name>}{<params>}
<block>
\ENDFUNCTION
# A <comment> is:
\COMMENT{<text>}
A <text>
, <block>
, or <condition>
may include the following:
% Normal characters
Hello world
% Escaped characters
\\, \{, \}, \$, \&, \#, \% and \_
% Math formula
$i \gets i + 1$
% Function call
\CALL{<func>}{<args>}
% Keywords
\AND, \OR, \XOR, \NOT, \TO, \DOWNTO, \TRUE, \FALSE, \BREAK, \CONTINUE
% LaTeX's sizing commands
\tiny, \scriptsize, \footnotesize, \small \normalsize, \large, \Large, \LARGE,
\huge, \HUGE
% LaTeX's font declarations
\rmfamily, \sffamily, \ttfamily
\upshape, \itshape, \slshape, \scshape
\bfseries, \mdseries, \lfseries
% LaTeX's font commands
\textnormal{<text>}, \textrm{<text>}, \textsf{<text>}, \texttt{<text>}
\textup{<text>}, \textit{<text>}, \textsl{<text>}, \textsc{<text>}
\uppercase{<text>}, \lowercase{<text>}
\textbf, \textmd, \textlf
% And it's possible to group text with braces
normal text {\small the size gets smaller} back to normal again
Note Although pseudocode.js recognizes some LaTeX commands, it is by no means a full-featured LaTeX implementation in JavaScript. It only support a subset of LaTeX commands that are most relevant to typesetting algorithms.
To display the caption of an algorithm, use algorithm
environment as a 'float' wrapper :
\begin{algorithm}
\caption{The caption of your algorithm}
\begin{algorithmic}
\STATE ...
\end{algorithmic}
\end{algorithm}
pseudocode.renderElement
can accept an option object as the last argument, such as
pseudocode.renderElement(document.getElementById("quicksort"),
{ lineNumber: true });
The following options are currently supported:
captionCount
: Reset the caption counter to this number.commentDelimiter
: The delimiters used to start and end a comment region. Note that only line comments are supported.indentSize
: The indent size of inside a control block, e.g. if, for etc. The unit must be in 'em'.lineNumber
: Whether line numbering is enabled.lineNumberPunc
: The punctuation that follows line number.noEnd
: Whether block ending, likeend if
, end procedure`, etc. are showned.titlePrefix
: The title prefix (defaults to "Algorithm") for captions.
The default values of these options are:
var DEFAULT_OPTIONS = {
indentSize: '1.2em',
commentDelimiter: '//',
lineNumber: false,
lineNumberPunc: ':',
noEnd: false,
captionCount: undefined
};
The above-mentioned global options may be overridden on a per-element basis
using HTML data-*
attributes
on the <pre>
DOM element.
The following example demonstrates how to enable line numbers and change title prefix:
<pre id="quicksort" class="pseudocode"
data-line-number=true data-title-prefix="Algo">
...
</pre>
pseudocode.js is written in JavaScript and built with Node.js. So, make sure you have Node.js installed before building pseudocode.js.
To compile the project on Ubuntu Linux, run the following commands in terminal:
cd pseudocode.js/
npm install
make
Then, open one of the sample documents:
build/katex-samples.html
, orbuild/mathjax-v2-samples.html
, orbuild/mathjax-v3-samples.html
in your favorite browser to check if the algorithms are typeset correctly.
pseudocode.js was originally written by Tate Tian (@tatetian). Together with @ZJUGuoShuai, I (@SaswatPadhi) added the MathJax support, and I am the current maintainer of this project. Suggestions, bug reports and pull requests are most welcome.
pseudocode.js is partially inspired by KaTeX. Thanks Emily Eisenberg(@xymostech) and other contributors for building such a wonderful project.