Re: question about matrix
- To: mathgroup at smc.vnet.net
- Subject: [mg63846] Re: [mg63832] question about matrix
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Thu, 19 Jan 2006 00:02:42 -0500 (EST)
- Reply-to: hanlonr at cox.net
- Sender: owner-wri-mathgroup at wolfram.com
m={{a[1,1],0,a[1,3],0,a[1,5]}, {a[2,1],0,a[2,3],0,a[2,5]}, {a[3,1],0,a[3,3],0,a[3,5]}, {0,0,0,0,0}, {a[5,1],0,a[5,3],0,a[5,5]}}; fm=Transpose[Select[Transpose[ Select[m,Union[#]!={0}&]], Union[#]!={0}&]] {{a[1, 1], a[1, 3], a[1, 5]}, {a[2, 1], a[2, 3], a[2, 5]}, {a[3, 1], a[3, 3], a[3, 5]}, {a[5, 1], a[5, 3], a[5, 5]}} fm==Transpose[DeleteCases[Transpose[ DeleteCases[m,{(0)..}]],{(0)..}]] True fm==Transpose[Transpose[m/. {(0)..}:>Sequence[]]/. {(0)..}:>Sequence[]] True Bob Hanlon > > From: "Tun Myint Aung" <tma at nus.edu.sg> To: mathgroup at smc.vnet.net > Subject: [mg63846] [mg63832] question about matrix > > > Dear Mathgroup, > > I have a matrix and it may have rows and columns which are zeros. I > can drop the rows and columns manually but it is troublesome. So my > question is that how to drop the rows and columns that are zeros > automatically. > > Best Regards, > > Tun Myint Aung > Graduate Student > National University of Singapore > E1A #02-18 > Kent Ridge, 119260, Singapore > E-mail g0202015 at nus.edu.sg <mailto:g0202015 at nus.edu.sg> > > > > >