XML in a Nutshell, 3rd Edition

Mathematical Operators

The Mathematical Operators block, shown in Table 27-27, contains a wide variety of symbols used in higher mathematics. A few of these symbols superficially resemble letters in other blocks. For instance, in most fonts, character 2206, , is virtually identical to the Greek capital letter delta. However, using characters in this block is preferable for mathematical expressions, as it allows software to distinguish between letters and mathematical symbols. Fonts may use the same glyph to represent different code points in cases like this.

Table 27-27. The Mathematical Operators block of Unicode

Unicode 3.1 added one more block of mathematical alphanumeric symbols in Plane 1 between 0x1D400 and 0x1D7FF, as shown in Table 27-28. Mostly these are repetitions of the ASCII and Greek letters and digits in what would normally be considered font variations. For instance, 0x1D400 is mathematical bold capital A. The justification for these is that when used in an equation, they really aren’t the same characters as the equivalent glyphs in text.

Table 27-28. The Mathematical Alphanumeric Symbols block of Unicode