\title{Retrieve sample contributions stored in an \code{\link{IcaSet}} object
  as a list.}
\description{This generic function retrieves, from an IcaSet object,
  the sample contributions contained in
  the attribute \code{A} as
  a list where sample IDs are preserved.
  \item{object}{Object of class \code{IcaSet}.}
  \code{Alist} returns a list whose length equals the number of
  components contained in the \code{IcaSet} object. Each element of this
  list contains a vector of sample contributions 
  indexed by the sample IDs.
\author{Anne Biton}