Re: Problems with recursive function

*To*: mathgroup at smc.vnet.net*Subject*: [mg87400] Re: Problems with recursive function*From*: Frank Hechtner <frank.hechtner at rub.de>*Date*: Wed, 9 Apr 2008 05:58:02 -0400 (EDT)*References*: <ftfela$bv1$1@smc.vnet.net> <ftfk9j$fav$1@smc.vnet.net>

hi daniel, thanks four your help. that?s the missing information i was searching for. You?re right, it would be better, to store each intermediate value. Kind regards from germany frank > Hi Frank, > > if I understand correctly, you need to define a recursion with a stop > > criterion. You can do this by e.g.: > > test[0,_]:=5; > > test[n_,b_]:=test[n-1,b] b; > > test[10,5] > > if you have many calculations, it may be advantageously to store > > intermediate results: > > test[n_,b_]:=test[n-1,b]=test[n-1,b] b; > > hope this helps, Daniel > > > > Frank Hechtner wrote: > >> Dear Newsgroup, > > >> I'm in trouble with a recursive function. the functios looks similar to > >> test[a_, b_] := test[a - 1, b]*b. A is the index b should just be an > >> argument of test. > >> for any calculation i need to tell mathematica the first value of the > >> function, e.g. test[0, 5]=5. The problem is the following: the first > >> object is independent of b. does anyone know a way to tell mathematica > >> the following thing: > > >> test[0,b]=5 => test[0]=5 regardless to b. > > >> Thanks for your help. > > >> Frank > > > >