Re: Defining a function P[A_ | B_]:=f[A,B] overriding Alternatives

*To*: mathgroup at smc.vnet.net*Subject*: [mg19241] Re: [mg19205] Defining a function P[A_ | B_]:=f[A,B] overriding Alternatives*From*: Carl Woll <carlw at u.washington.edu>*Date*: Wed, 11 Aug 1999 02:06:53 -0400*Organization*: Physics Department, U of Washington*References*: <199908100652.CAA18375@smc.vnet.net.>*Sender*: owner-wri-mathgroup at wolfram.com

Peltio, Why don't you use one of Mathematica's other characters instead, such as esc | esc, which can also be entered in as \[VerticalSeparator]. One thing to note here is that p[a_ esc | esc b_] is automatically parsed as p[VerticalSeparator[a_,b_]]. Carl Woll Dept of Physics U of Washington Peltio wrote: > Is there a general way to call a function with arguments separated not by > commas but by user defined symbols (particularly Mathematica sacred symbols) > ? > _________________________________________________ > > Here's what I mean: > I was willing to define a function for the calculation of the conditional > probabilty, via the Bayes formula, and I wanted to define it in such a way > that the function call would be: > > p[A|B] > > but Mathematica correctly interpreted the lhs of the definition > p[A_|B_] as if there were two alternative arguments. > I can unprotect Alternatives and clear it and that would work, > > Unprotect[Alternatives]; > Clear[Alternatives]; > p[A_|B_]:= {A,B} > > p[A|B] > {A,B} > > but, is there a less traumatic way to achieve this without fully sacrificing > Alternatives? It would be fine to avoid its evaluation only when inside a > [ ] function, by means of upvalues. But the following does not seems to > work: > > Unprotect[Alternatives]; > Alternatives /: p[A_|B_]:={A,B} > > And yet I wanted to be able to define my function without showing the > Alternatives /: part. Is there a way to inhibit the Alternatives evaluation > inside p[] in a single statement (that could be hidden in a initialization > cell)? > > Thanks for any help. > Peltio > peltio AT usa DOT net > > Please don't do a reply to : spammers forced me to hide my address. Use > insted the address shown above substituting @ to AT and . to DOT. -- Carl Woll Dept of Physics U of Washington