0.2 Displaying mathematical content  (Page 2/3)

Mathml elements

There are scores of elements in MathML. They are grouped under two broad headings :

1. Presentation elements
2. Content elements

Presentation elements describe visual represntation of mathematical notation or content in a two-dimensional plane. In other words, these elements emphasize the visual attributes like size, color, alignment and relative postions. The content elements, on the other hand, emphasize the mathematical “sense” of the expression. There are nearly 30 presentation elements and 50 attributes. Content elements are more in numbers - about 120, but they accept only about a dozen attributes.

Presentation elements

Presentation elements fall under following categories :

1: Token elements : These elements display data and text. We must know that the token elements are the only MathML elements permitted to contain character data. It is relevant to know that MathML character data set is Unicode characters, which are about 900 in numbers. In total, the token elements are seven (7) in numbers. The names and their basic role in rendering content are listed here :

Token elements

• mi : renders identifires and symbols
• mn : renders numbres
• mo : renders mathematical opreators
• mtext : renders text
• mspace : creates space in both horizontal and vertical directions
• ms : renders content for processing by other programs
• mglymph : enables creating new characters

2: Layout elements : They serve as placeholders for text and data at different levels of display matrix or as mechnism to distribute mathematical content in two dimensional space. There are three broad categories of layout elements :

(i) Basic layout elements : They provide basic frame work for structuring mathematical expression in two dimensional space. The basic layout elements are ten (10) in numbers. The names and their basic role in rendering layout are listed here :

Basic layout elements

1. “mrow” : makes horizontal groups of sub-expressions for variety of purposes
2. mfrac : renders elements in $\frac{P}{Q}$ form
3. msqrt : renders a square root
4. mroot : renders a radical with an index
5. mstyle : sets style attributes for the enclosed elements
6. merror : enclose a syntax error message from a preprocessor
7. mpadded : manages space around content by manipulating the size of box surrounding content
8. mphantom : makes content invisible, while maintaining structure
9. mfenced : surrounds its content with a pair of fences and segregates content's terms with separators
10. menclose : enclose content with a stretching symbol

(ii) Scripting elments : They provide the mechanism to render sub and super script, under and over scipt and such other scripting lay out. , under proviides For example, msup and msub provide mechanism to script a base character with a pair of scripting characters such as $v_{}^2$ and $A_1^{}$ . The scripting lay out elements are seven (7) in numbers. The names and their basic role in rendering layout are listed here :

Basic layout elements

1. msub : displays subscript
2. msup : displays superscript
3. msubsup : displays sub and super script simultaneously
4. munder : displays under script
5. mover : displays over script
6. munderover : displays under and over script simultaneously
7. mmultiscripts : displays multiple vertically sub and super scripts simultaneously