> On 20 Jul 2015, at 18:37, Aditya Mahajan <[email protected]> wrote:
> 
> On Mon, 20 Jul 2015, Hans Aberg wrote:
> 
>> 
>>> On 20 Jul 2015, at 16:40, Aditya Mahajan <[email protected]> wrote:
>>> On Mon, 20 Jul 2015, Hans Aberg wrote:
>>>> The LaTeX package unicode-math has an option colon=literal, which makes it 
>>>> behave as in math functions (as in example below). Has ConTeXt a similar 
>>>> option?
>>> No. You have to use \colon.
>> 
>> It would be nice with such an option, as it helps the readability of the 
>> input files.
> 
> There are two uses of colon in math, as a relation (in sets \{ x : f(x) = 0 
> \} and in ratios A:B, etc) and as a punctuation ($f \colon A -> B, etc.[1]). 
> Only one of them can be mapped to the literal :, the other must use a macro 
> name. Knuth chose to map : to the relation and mapped \colon to a punctuation 
> and every other macro package follows that convention.

Right. Perhaps he didn’t use functions much. :-)

> It is easy to change the mapping, but if the mapping is reversed, is there is 
> standard name for : as a relation?

It seems that “\:” might be used. I get an error when trying to use it in 
luatex. But note:

In pure math, “:” is also used for projective coordinates, it does not seem to 
have operator spaces around them. This is what I think is the right look:
  https://en.wikipedia.org/wiki/Homogeneous_coordinates#Notation

There is also Unicode ∶ RATIO U+2236.

So a proposal might be to keep \colon, and make a new \ratio for those that 
want to use the operator : in ASCII. The : without spaces might perhaps be 
called \proj or something.

Looking at
  https://en.wikipedia.org/wiki/Mathematical_Operators
a UTF-8 mapping would be sending U+2236 to \ratio, the operator :. There is no 
special colon for the other uses, function and projective coordinates, it seems.

So the \: might be mapped to \proj or \ratio according to taste.


___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the 
Wiki!

maillist : [email protected] / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________

Reply via email to