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Re: insert vector in a 4D array
Posted:
Jun 26, 2011 6:50 AM


Thanks for proposing this solution but I was thinking more of a durect substitution for replacing the first line in each array for all dimensions, something like
A(1.:.:.:)=V which does not work
"Nasser M. Abbasi" <nma@12000.org> wrote in message <iu6cnn$qa6$1@speranza.aioe.org>... > On 6/25/2011 8:25 PM, Nasser M. Abbasi wrote: > > On 6/25/2011 6:31 PM, Michel wrote: > >> I have a 4D array size [367 41 25 15] and would like to insert the vector [1961:2001] in > >> the first line of the first dimension. > >> How can I do it? > >> Thanks > > > > > > If A was the 4D array, and v is the above vector, then try > > > > A(1,:,1,1)=v > > > > Nasser > > btw, I understood what you wanted is to replace only the first row > in first matrix by v. > > If you meant to replace EACH first row in each matrix in each higher > dimension, then may be double loop might be an easy way to do it > otherwise you have to do reshape and such and put things back. > > But I think loop is easier in this case: > >  > A=rand(367,41,25,15); > > third_diemension=25; > fourth_diemension=15; > > v=1961:2001; > for i=1:third_diemension > for j=1:fourth_diemension > A(1,:,i,j)=v; > end > end >  > > You can interchange the order of the 'j', 'i' above to see > if you might get a difference in performance. But for such > small matrix size (45 MB?), it should not matter. > > May be an expert will show us a shorter or better way. > > Nasser



