[R] Embedding lists in matrices and matrices in lists

[Michael Kogan]

Hi,

I'm new to programming, new to R and even new to mailing lists so please 
be patient with me. I need to manage many matrices generated by an R 
program. These matrices have different dimensions and I'd like to group 
them somehow. The best way would be to have a big matrix (let's call it 
database) where every element database[x,y] consists of a list of 
matrices that all have the dimensions ncol(matrix1)=x and 
nrow(matrix1)=y. So those matrices have to be embedded into lists and 
the lists have to be embedded in the big database matrix. If I simply try

    database=matrix(0,10,10)
    database[4,4]=c(matrix1,matrix2)

I get

    Error in database[4, 4] = c(matrix1, matrix2) :
      number of items to replace is not a multiple of replacement length
    Execution halted

which makes sense of course... Is there any possibility to make this 
work? Or maybe there is a better way to organize those matrices?

Regards,
Michael