Re: ListCorrelate and functions on it with an extra condition
- To: mathgroup at smc.vnet.net
- Subject: [mg86344] Re: [mg86322] ListCorrelate and functions on it with an extra condition
- From: Carl Woll <carlw at wolfram.com>
- Date: Sun, 9 Mar 2008 05:00:22 -0500 (EST)
- References: <200803081043.FAA13470@smc.vnet.net>
P_ter wrote: >Hello, >I have a question about the function p in the following: >ListCorrelate[{{1, 1}, {1, 1}}, {{a1, b1, c1, d1}, {a2, b2, c2,d2}}, {1, -1}, {}, Times, p] >The outcome is: >{{p[p[a1, b1], p[a2, b2]], p[p[b1, c1], p[b2, c2]],p[p[c1, d1], p[c2, d2]]}} >I have the following problem with p[p[a1, b1], p[a2, b2]]. >If a1!=b1 then the "outer"p should give False, >if a1==b1 and a2==b2 then the outer p should give True, >if a1==b1 and a2!=b2 but Length[a2] < Length[b2], the outer p should give True, >for the rest the outer p should give False. >Any idea? >with friendly greetings, >P_ter > > What's wrong with: p[p[a1_, a1_], p[a2_, a2_]] = True p[p[a1_, a1_], p[a2_, b2_]] := Length[a2] < Length[b2] p[_p, _p] = False ? Carl Woll Wolfram Research
- References:
- ListCorrelate and functions on it with an extra condition
- From: P_ter <peter_van_summeren@yahoo.co.uk>
- ListCorrelate and functions on it with an extra condition