Fractions

• abc/d gives 
• More complicated operands use parentheses ( ), brackets [ ], or { }
• Outermost parents aren't displayed in built-up form 
• E.g., plain text (a + c)/d displays as
• Easier to read than TEX's, e.g., {a + c \over d}
• MathML:
  <MFRAC>
  <MROW> <I>a</MI> <O>+</MO> <I>c</MI> </MROW>
  <MROW> <I>d</MI> </MROW>
  </MFRAC>
• Neat feature: plain text looks like math

For more complicated operands, such as those that include operators, parentheses ( ), brackets [ ], or { } can be used to enclose the desired character combinations. If parentheses are used and the outermost parenthesis set is preceded and followed by operators, that set is not displayed in built-up form, since usually one doesn't want to see such parentheses. So the plain text (a + b)/cI, where the / is U+2044, displays as shown in the slide.

In practice, this approach leads to plain text that is significantly easier to read than TeX's, e.g., {a + c \over d} , since in many cases, outermost parentheses are not needed, while TeX requires { }'s except for single letters. To force the display of an outermost parenthesis set, one encloses the set, in turn, within parentheses, which then become the outermost set. A really neat feature of this notation is that the plain text is, in fact, a legitimate mathematical notation in its own right, so it's relatively easy to read.