Converting float to double.

[Ronald J. Legere]

 I have a very simple question. What is the best way to 
convert a float to a double?
 I use fromRational.toRational, and the notes in the prelude
seem to imply that this is optimized into something sensible..
is this the way?

Cheers! +++++++++++++++++++++++++++++++++++++++++++++++++ Ron Legere --
http://www.its.caltech.edu/~legere Caltech Quantum Optics MC 12-33
Pasadena CA 91125 626-395-8343 FAX: 626-793-9506
+++++++++++++++++++++++++++++++++++++++++++++++++