[sage-devel] Re: Pattern matching in Sage

2017-11-17 Thread rjf
It includes this probably bad idea --- "Often, tree-walkers would prefer to see divisions instead of multiplications and negative exponents" which means that a programmer may have to write the same code twice. Example: Once for exp(-x) and once for 1/exp(x). or for 2^(-x), or even 2^n

[sage-devel] Re: Pattern matching in Sage

2017-11-17 Thread Eric Gourgoulhon
Le dimanche 12 novembre 2017 16:04:38 UTC+1, Eric Gourgoulhon a écrit : > > > Yes for sure, I will rewrite it using the expression tree walker, but in > another ticket. > This is now #24232 . This ticket rebases all simplifications in calculus on

[sage-devel] Re: Pattern matching in Sage

2017-11-16 Thread rjf
On Wednesday, November 15, 2017 at 12:07:45 AM UTC-8, Dima Pasechnik wrote: > > I would not be too surprised if someone had written a Lisp interpreter > in Python, representing Lisp code as stings :-) There is a certain universality in strings, given that humans read and write strings of

[sage-devel] Re: Pattern matching in Sage

2017-11-15 Thread Dima Pasechnik
I would not be too surprised if someone had written a Lisp interpreter in Python, representing Lisp code as stings :-) -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an

[sage-devel] Re: Pattern matching in Sage

2017-11-14 Thread rjf
It seems to me that the use of python matching programs for implementing Rubi suggest that this (or other?) matching programs were too slow to be effective. From a brief scan through the papers, it seems that the authors do not compare their programs with programs that have been written by

[sage-devel] Re: Pattern matching in Sage

2017-11-12 Thread Eric Gourgoulhon
Hi, Le dimanche 12 novembre 2017 14:45:54 UTC+1, Ralf Stephan a écrit : > > Is the documentation really so bad that you couldn't find > > http://doc.sagemath.org/html/en/reference/calculus/sage/symbolic/expression_conversions.html > > Of course Sage uses pattern matching, e.g. to convert

[sage-devel] Re: Pattern matching in Sage

2017-11-12 Thread Ralf Stephan
Is the documentation really so bad that you couldn't find http://doc.sagemath.org/html/en/reference/calculus/sage/symbolic/expression_conversions.html Of course Sage uses pattern matching, e.g. to convert expressions. I'm not reverting that positive on that ticket but I urge the author to