Simple stored procedure-like function in PostgreSQL?

Question

I want to create a function in pgsql that will take three parameters and return a single value (1 row, 1 col).

I have the query working but can not seem to find a proper example of creating a function to do this.

Answer 1

Take a look at the example on this page, or this one.

If you actually go through the documentation there are multiple example of various functions and return types.