Scalable Vector Graphics (SVG) and MathML (Mathematical Markup Language) are XML
applications that are widely used in scientific contexts. SVG is used to draw
vector graphics, and is frequently found in visualization libraries such as ProtoVis.
MathML is used to describe the presentation and meaning of mathematical
formula. They are very easy to work with in a programmatic sense, because they
are XML-based and therefore just text, and yet they are capable of rendering
beautiful information in supporting web browsers.
In the beginning of the process, HTML5 was not extensible,
and to this day it remains opposed to the whole namespace idea. But SVG and
MathML are highly popular and useful XML applications that deserve a place
within the HTML5 spec. And so shall it be: <svg> and <math> are the
opening volleys in inserting SVG and MathML into your HTML5 document tree. Any
elements that are children of the SVG and MathML specs are valid and functional
child elements of the <svg> and <math> elements respectively. No
need to declare a namespace.
Most of the web browsers can display MathML tags. If your
browser does not support MathML, then I would suggest you to use latest version
focuses on the display of an equation, and has about 30 elements. The elements'
names all begin with m. A Presentation MathML expression is built up out of
tokens that are combined using higher-level elements, which control their
layout (there are also about 50 attributes, which mainly control fine details).
generally only contain characters (no other elements). They include:
<mi>x</mi> – identifiers;
<mo>+</mo> – operators;
<mn>2</mn> – numbers.
zero</mtext> – text.
Note however that these
token elements may be used as extension points, allowing markup in host
languages. MathML in HTML5 allows most inline HTML markup in mtext, and
is conforming, with
the HTML markup being used within the MathML to mark up the embedded text
(making the first word bold in this example).
These are combined using layout elements that generally
contain only elements. They include:
<mrow> – a
horizontal row of items;
<munderover> , and others – superscripts, limits over and under operators
like sums, etc;
<mroot> – roots;
surrounding content with fences, such as parentheses.
As usual in HTML and
XML, many entities are available for specifying special symbols by name, such
as π and →. An interesting feature of MathML is that
entities also exist to express normally-invisible operators, such as
⁢ for implicit multiplication.
Thus, the expression requires two layout elements: one to
create the overall horizontal row and one for the superscripted exponent.
Including only the layout elements and the (not yet marked up) bare tokens, the
structure looks like this:
a ⁢ <msup>x
+ b ⁢ x
individual tokens also have to be identified as identifiers (mi), operators
(mo), or numbers (mn). Adding the token markup, the full form ends up as:
<mi>a</mi> <mo>⁢</mo> <msup><mi>x</mi><mn>2</mn></msup>
A valid MathML document typically consists of the XML
declaration, DOCTYPE declaration, and document element. The document body then
contains MathML expressions which appear in <math> elements as needed in
the document. Often, MathML will be embedded in more general documents, such as
HTML, DocBook, or other XML schemas. A complete document that consists of just
the MathML example above is shown here:
PUBLIC "-//W3C//DTD MathML 2.0//EN"