Hello, Actually Im aware that it is impossible to turn back to original version. The project owners agree on that and thats is why they accept results which are closer to the original one. However I need to make a factorization anyway. My suggestion is at least saving some small information to the DNF string like number of distributions. for example for a(b+c(d+e)) it is 2. so when Im making translation back to original, I will know that I will make one factorization, then one more because number is 2. However these steps make me confused, working with matrices, creating submatrices, make changes on them... that is why I wanted to find alternative ways. I dont think I can define a grammar like that. but wanted to ask the group if that's possible in Antlr. until I find out that, I will keep on working matrices I guess.
thanks for answers by the way for all > Date: Thu, 18 Mar 2010 08:59:00 -0700 > From: [email protected] > To: [email protected] > Subject: Re: [antlr-interest] Factorization of Logic Expressions > > I'm confused (not an abnormal condition) > > If I understand it, you start with a logical expression, parse, factor > then save it. The question is how to recover the original, right? > > If that is the problem, I'd say it is impossible. The original parse > operation is a many to one transform as is the factoring. So given a > factored expression, I don't see a way to choose among the many possible > original expressions. > > If I am understanding what you're trying to do, it would seem you have a > couple of choices: > You could define some sort of canonical expression ie: factored, or > expanded and call it "equivalent" or you can save additional information > on the transforms you have done to arrived at the factored. > > Good luck, > Joe > > John B. Brodie wrote: > > On Thu, 2010-03-18 at 07:56 +0000, Nazim Oztahtaci wrote: > > > >> hi, > >> > >> I guess my point is misunderstood. for example, my output is smt like > >> abc+abd and this is the only information I save on a text file. Later > >> on I will read this string, no more information I know about original > >> diagram or what I did for DNF transformation. My program reads this > >> string and factorize it to ab(c+d). I need to read all minterms, make > >> some calculations(either in a matrix or there can be co-graphs > >> maybe).I dont think I can use Antlr because I cant define this in a > >> grammar, at least on my mind. > >> > > > > Sorry. I misunderstood what you are trying to do. My previous > > suggestions are not relevant to your problem. Sorry. > > > > -jbb > > > > > > > > List: http://www.antlr.org/mailman/listinfo/antlr-interest > > Unsubscribe: > > http://www.antlr.org/mailman/options/antlr-interest/your-email-address > > > > List: http://www.antlr.org/mailman/listinfo/antlr-interest > Unsubscribe: > http://www.antlr.org/mailman/options/antlr-interest/your-email-address _________________________________________________________________ Yeni Windows 7: Size en uygun bilgisayarı bulun. Daha fazla bilgi edinin. http://windows.microsoft.com/shop List: http://www.antlr.org/mailman/listinfo/antlr-interest Unsubscribe: http://www.antlr.org/mailman/options/antlr-interest/your-email-address -- You received this message because you are subscribed to the Google Groups "il-antlr-interest" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/il-antlr-interest?hl=en.
