RE: Changing delayed formula

*To*: mathgroup at smc.vnet.net*Subject*: [mg35473] RE: [mg35461] Changing delayed formula*From*: "DrBob" <majort at cox-internet.com>*Date*: Sun, 14 Jul 2002 06:19:48 -0400 (EDT)*Reply-to*: <drbob at bigfoot.com>*Sender*: owner-wri-mathgroup at wolfram.com

des = {{11, 12, 13, 14}, {21, 22, 23}, {31, 32}, {41, 42, 43, 44, 45}} Distribute[des, List] Bobby Treat -----Original Message----- From: Julio Vera [mailto:jvera at adinet.com.uy] To: mathgroup at smc.vnet.net Subject: [mg35473] [mg35461] Changing delayed formula Hi, I have a list of lists. it's length (the number of sublists it contains) varies. In[1]:= des={{11,12,13,14},{21,22,23},{31,32},{41,42,43,44,45}} Out[1]:= {{11,12,13,14},{21,22,23},{31,32},{41,42,43,44,45}} The length of each of the sublists is arbitrary, too. So I have this list of lengths. In[2]:= elems=Flatten[Table[Dimensions[des[[i]]],{i,Length[des]}]] Out[2]:= {4,3,2,5} I want to obtain the list of all combinations of one element of each sublist, bounded by &&. This will be a list of 120 elements, each of them with 4 components. I define a delayed formula, and apply Array to it (the characters printed as bold are subscripts in the Mathematica notebook). In[3]:= cond4[a_,b_,g_,d_]:=des[[1,a]]&&des[[2,b]]&&des[[3,g]]&&des[[4,d]] In[4]:= combi=Flatten[Array[condLength[des],elems]] Out[4]:= {11&&21&&31&&41,11&&21&&31&&42,11&&21&&31&&43,11&&21&&31&&44,... ...14&&23&&32&&42,14&&23&&32&&43,14&&23&&32&&44,14&&23&&32&&45} Since the length of des varies, I would have to define cond each time. For instance: cond3[a_,b_,g_,d_]:=des[[1,a]]&&des[[2,b]]&&des[[3,g]] I would like to make a definition for cond that would adapt to these changes automatically. I arrived to this solution, which is not rejected by Mathematica, but does not work, either. In[5]:= d[a_,b_]:=des[[a,b<>"_"]] In[6]:= Unprotect[ReplaceAll] Out[6]:= {ReplaceAll} In[7]:= condLength[des][Table[FromCharacterCode[944+i]<>"_",{i,Length[des]}]]/.{ a__}=AEa:=Apply[And,Table[d[i,FromCharacterCode[944+i]<>"_"],{i,Length[d es]}]] In fact, I quit the kernel and rerun all the cells except the one written here as In[3]. If not, the definition for cond4 remains as it was. I was not able to clear cond4 individually. Thanks very much for anything you can suggest. Best regards, Julio Vera