[R] A basic design question for R

[Petr Savicky]

On Sat, Jun 16, 2012 at 06:14:38PM +0100, Onur Uncu wrote:
> Thank you.  But isn't a data frame already a list?

Data frame is a list of columns. The suggestion was to use a list,
whose length is the number of rows and which contains a matrix
for each row.

> What is wrong with
> adding a column to the existing data frame (a column with the
> mortality curve matrices)?

The elements of a data frame cannot be matrices. If the matrices
may be unfolded to vectors, then these vectors can be included
into the rows. Something like

  Gender  Age  x1  x2  x3  y1  y2  y3
   M      70   ...
   F      65   ...
   M      70   ...

where ... represent six numbers in each row, which form a matrix

  x1  y1
  x2  y2
  x3  y3

However, i think, a list of matrices is more flexible.

Petr Savicky.