An object of this class is a convenient way of storing
  (and later plotting, editing, etc)
  a set of functions $f_{i,j}(r)$ of a real argument $r$,
  defined for each possible pair $(i,j)$ of indices
  $1 \le i,j \le n$. We may think of this
  as a matrix or array of functions $f_{i,j}$.  Function arrays are particularly useful in the 
  analysis of a multitype point pattern (a point pattern in which 
  the points are identified as belonging to separate types).
  We may want to compute a summary function for the points
  of type $i$ only, for each of the possible types $i$.
  This produces a $1 \times m$ array of functions.
  Alternatively we may compute a summary function
  for each possible pair of types $(i,j)$.
  This produces an $m \times m$ array of functions.
  For multitype point patterns the command alltypes
  will compute arrays of summary functions for each possible
  type or for each possible pair of types.
  The function alltypes 
  returns an object of class "fasp".
  An object of class "fasp" is a list containing at least the
  following components:
  [object Object],[object Object],[object Object],[object Object],[object Object]