cast type bytea to double precision

HI All,

I have a database column which type is bytea. It contains floats converted
as byte array (4 bytes per one float) and encoding is Escape. I would be
able to get corresponding bytea string using substring function.

My question is how can I convert bytea string to float inside a SQL
function. Earlier I converted to float in C# side. I used
dataReader.getByte method to retrieve bytes and then Converted to float
using BitConverter.ToSingle (.Net build in class) method.

Now I can't use intermediate component as Npqsql driver. I want SQL to
directly convert bytea into floats and return the corresponding number when
execute a query from 3rd party application.

Thanks and Regards
Amila Jayasooriya