Re: [R] Elegant way to subtract matrix from array

2011-07-27 Thread Erich Neuwirth
A-kronecker(rep(1,10),S) kronecker(m1,m2) creates a "tiled" matrix each element of m1 in replaced by m2 multiplied with the element of m1 m1 = (1 2) (3 4) m2 = (11 12) (13 14) kronecker(m1,m2) therefore is 1 * (11 12)2 * (11 12) (13 14)(13 14) 3 * (11 12)

Re: [R] Elegant way to subtract matrix from array

2011-07-27 Thread steven mosher
Thanks Gabor! On Wed, Jul 27, 2011 at 3:08 AM, Gabor Grothendieck wrote: > On Wed, Jul 27, 2011 at 4:06 AM, steven mosher > wrote: > > there are really two related problems here > > > > I have a 2D matrix > > > > > > A <- matrix(1:100,nrow=20,ncol =5) > > > > > > S <- matrix(1:10,nrow=2,ncol

Re: [R] Elegant way to subtract matrix from array

2011-07-27 Thread Gabor Grothendieck
On Wed, Jul 27, 2011 at 4:06 AM, steven mosher wrote: > there are really two related problems here > > I have a 2D matrix > > > A <- matrix(1:100,nrow=20,ncol =5) > > > S <- matrix(1:10,nrow=2,ncol =5) > > > #I want to subtract S from A. so that S would be subtracted from the > first 2 rows of > >

Re: [R] Elegant way to subtract matrix from array

2011-07-27 Thread steven mosher
Cool, I looked at sweep but didnt consider it as I thought it was restricted to certain functions. So thanks for that solution. yes the data is very large and the future work will increase 10 fold, as for the matrix one I'm not too keen on replicating the smaller matrix, I've had one guy usin

Re: [R] Elegant way to subtract matrix from array

2011-07-27 Thread Gavin Simpson
On Wed, 2011-07-27 at 01:06 -0700, steven mosher wrote: > there are really two related problems here > > I have a 2D matrix > > > A <- matrix(1:100,nrow=20,ncol =5) > > > S <- matrix(1:10,nrow=2,ncol =5) > > > #I want to subtract S from A. so that S would be subtracted from the > first 2 row

[R] Elegant way to subtract matrix from array

2011-07-27 Thread steven mosher
there are really two related problems here I have a 2D matrix A <- matrix(1:100,nrow=20,ncol =5) S <- matrix(1:10,nrow=2,ncol =5) #I want to subtract S from A. so that S would be subtracted from the first 2 rows of #A, then the next two rows and so on. #I have a the same problem with a 3D