Scalar function to reduce all repeating space characters down to a single space character

dbo.deDupeSpaces.sql

CREATE FUNCTION [dbo].[deDupeSpaces] 
(
	@input nvarchar(500)
)
RETURNS nvarchar(500)
AS
BEGIN
    /**
    *  Based on Nigel Rivett's SQL script found: 
    *    http://www.nigelrivett.net/SQLTsql/RemoveNonNumericCharacters.html 
    */
	DECLARE @i int

	set @i = patindex('%[ ][ ]%', @input)
	while @i > 0
	begin
		set @input = replace(@input, '  ', ' ')
		set @i = patindex('%[ ][ ]%', @input)
	end

	RETURN @input

END