arrays of floating point numbers / linear algebra operations into the DB

Hello,
I'd like to perform linear algebra operations on float4/8 arrays.  
These tasks are tipically carried on using ad hoc optimized libraries  
(e.g. BLAS). In order to do this, I studied a bit how arrays are  
stored internally by the DB: from what I understood, arrays are  
basically a vector of Datum, and floating point numbers are stored by  
reference into Datums. At a first glance, this seem to close the  
discussion because in order to perform fast linear algebra operations,  
you need to store array items in consecutive memory cells.
What are the alternatives? Create a new specialized data type for  
floating point vectors?
Basically, the use-case is to be able to rescale, add and multiply  
(element-by-element)
vectors.

Thanks for your help,
e.