On 7/27/2010 3:02 PM, Kenneth Whistler wrote:
Karl Williamson asked:
Subject: Why does EULER CONSTANT not have math property and PLANCK CONSTANT
does?
They are U+2107 and U+210E respectively.
Because U+210E PLANCK CONSTANT is, to quote the standard,
"simply a mathematical italic h". It serves as the filler for
the gap in the run of mathematical italic letters at U+1D455.
Correct - they form a set and need to be treated consistently.
Other letterlike symbols in that block are not given the
Other_Math property, even if they may be used in mathematical
expressions. (Note that regular Greek letters are also not
given the Other_Math property, even though they obviously also
occur in mathematical expressions.)
For Euler Constant and Weierstrass elliptic function, this doesn't make
a lot of sense, as these are explicitly mathematical characters, not
characters that are "also used in mathematical expressions".
I have put in a formal proposal to add these two (2107 and 2118) to the
list of characters with the math property.
The Math property can be thought of as a hint that a particular
symbol is specialized for mathematical usage; it isn't a
property that any character that ever occurs in a mathematical
expression needs to have. Nor is every character with
the Math property only used in mathematical contexts.
One way to look at this property is as a way to help detection of
mathematical expressions in running text. Characters that are primarily
used for mathematical purposes, or prominently used there, should be
included. Characters that are heavily used in ordinary text, with
non-mathematical uses should be excluded.
A./
