Re: Recursion inspection technique : HoldForm but release variables
- To: mathgroup at smc.vnet.net
- Subject: [mg66425] Re: Recursion inspection technique : HoldForm but release variables
- From: Peter Pein <petsie at dordos.net>
- Date: Fri, 12 May 2006 02:03:00 -0400 (EDT)
- References: <e3um8v$hfr$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
flatmax schrieb: > Hi, > > If I define a recursion and hold its form to inspect it : > Clear[test] > test[j_Integer?Positive] := > test[j] = k[j] HoldForm[ test[j - 1] ] > > then This is what happens : > > In[22]:= test[4] > > Out[22]:= test[4 - 1] k[4] > > But I would like it to be with the variable evaluated : > > Out[22]:= test[3] k[4] > > Whats the trick ??? > > thanks > Matt > Hi Matt, another possibility is to Hold just the function's name: In[1]:= Clear[test] test[(j_Integer)?Positive] := test[j] = k[j]*HoldForm[test][j - 1] In[3]:= test[4] Out[3]= k[4]*HoldForm[test][3] (* displays as k[4]*test[3] *) hth, Peter