Strange behavior with comment
- To: mathgroup at smc.vnet.net
- Subject: [mg118655] Strange behavior with comment
- From: Virgil Stokes <vs at it.uu.se>
- Date: Fri, 6 May 2011 07:22:34 -0400 (EDT)
The following gives an error, m = 4; k = 3; IntegerPartitions[ m, {k}]; (* Get all integer partitions that are exactly of length k *) Permutations /@ %; (* Get all permutations of the integer partitions *) Flatten[%, 1] (* Flatten the list *) Apply[Multinomial, %, {1}] (* Apply Multinomial to each element of the list % *) ns = Plus @@ % Flatten::normal: Nonatomic expression expected at position 1 in Flatten[3,1]. >> Flatten[3, 1] However, if I remove the comment from the entry in the line before Flatten, then it gives the correct results, m = 4; k = 3; IntegerPartitions[m, {k}]; (* Get all integer partitions that are exactly of length k *) Permutations /@ %; Flatten[%, 1] (* Flatten the list *) Apply[Multinomial, %, {1}] (* Apply Multinomial to each element of the list % *) ns = Plus @@ % {{2, 1, 1}, {1, 2, 1}, {1, 1, 2}} {12, 12, 12} 36 Why does this happen?