Re: HELP: How to do count to the SUB-LIST
- To: mathgroup at smc.vnet.net
- Subject: [mg82193] Re: HELP: How to do count to the SUB-LIST
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Sun, 14 Oct 2007 06:15:32 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <fen5th$4ho$1@smc.vnet.net>
zhen wrote: > Hallo, everyone > > I am new to Mathematica, and I get one problem now, hope to get some > help here > > I got a list like this: > > {{0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, {0, 1, 1, 0, 0, 0, 1, 0, 0, 0}, > {0, 0, 0, 0, 1, 1, 0, 0, 2, 0}, {1, 0, 1, 0, 0, 1, 0, 1, 0, 0}, > {1, 3, 3, 4, 2, 2, 5, 3, 2, 1}, {7, 2, 2, 3, 4, 4, 0, 3, 1, 3}} > > I need to get a list to show the number of non zero number in each sub > list, as to say, I need to get a list like this: > > {0,3,3,4,10,9} For non-binary data, you could use one of the following: In[1]:= lst = {{0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, {0, 1, 1, 0, 0, 0, 1, 0, 0, 0}, {0, 0, 0, 0, 1, 1, 0, 0, 2, 0}, {1, 0, 1, 0, 0, 1, 0, 1, 0, 0}, {1, 3, 3, 4, 2, 2, 5, 3, 2, 1}, {7, 2, 2, 3, 4, 4, 0, 3, 1, 3}}; Length /@ (lst /. 0 -> Sequence[]) Length /@ DeleteCases[lst, 0, {2}] Plus @@@ Unitize /@ lst Out[2]= {0, 3, 3, 4, 10, 9} Out[3]= {0, 3, 3, 4, 10, 9} Out[4]= {0, 3, 3, 4, 10, 9} Regards, -- Jean-Marc