Re: List difference using patterns and substitutions.
- To: mathgroup at smc.vnet.net
- Subject: [mg71348] Re: List difference using patterns and substitutions.
- From: "dkr" <dkrjeg at adelphia.net>
- Date: Wed, 15 Nov 2006 06:44:31 -0500 (EST)
- References: <ejc53g$6qf$1@smc.vnet.net>
Nacho, A simple solution would be: In[17]:= f[a_List]:=Most[RotateLeft[a]-a]; In[18]:= f[{1,2,3,5,5}] Out[18]= {1,1,2,0} If you insist on using pattern matching, then you could try something like: In[19]:= g[a_List]:=Join[a,{{}}]//.{x_,y_,z___,{v___}}:>{y,z,{v,y-x}}//Last In[20]:= g[{1,2,3,5,5}] Out[20]= {1,1,2,0} dkr