Re: [Maxima-discuss] indexes and summation conventions / subscripts etc

[Michel T. <ta...@lp...>]

Le 16/12/2015 17:14, Richard Fateman a écrit :
> The Einstein convention may be handy, and it may have been more-or-less
> reasonably implemented in Maxima programs (I don't do relatively for a
> living)
> but in general it's not necessary to mimick exactly what works for
> paper.  Humans
> are more flexible than that, and a notation that doesn't play well on a
> computer
> should not be used by (physicists?) to insist that programmers should
>   hack endlessly on the program.  Especially if another, more
> suitable  (unambiguous in the context of other supported mathematics, say)
> is available.

Well i gave these examples from relativity since it is the only example 
i know where there is heavy use of up and down indices, and since Robert 
Dodier was providing a notation with 4 different positions of the index. 
Personnally i cannot think of any reasonable use of preindices, apart 
from the marginal example of the notation for hypergeometric functions. 
If simplicity is required, i think that only
one sort of index is really useful, in position post, down, since this 
is the most traditional notation throughout mathematics. However such an 
index may be a letter or a number.


> A mathematician of my acquaintance insisted that he couldn't use
> Macsyma/Maxima
> because the computer terminal I offered him was lacking in keys for
> Greek letters.
> Well, he was right in that indeed he couldn't use Maxima.

And indeed greek letters are in such universal use in mathematics and 
physics that having them at disposal seems necessary. But this is no 
more a problem nowadays, either in wxmaxima or using unicode as 
explained by Leo Butler.


-- 
Michel Talon