MSSQL - How to Check A Numeric Value

Here is a quick script (forgot where I found it) to check a given value is a numeric value:

CREATE FUNCTION dbo.isReallyNumeric

(

    @num VARCHAR(64)

)

RETURNS BIT

BEGIN

    IF LEFT(@num, 1) = '-'  SET @num = SUBSTRING(@num, 2, LEN(@num))

    DECLARE @pos TINYINT

    SET @pos = 1 + LEN(@num) - CHARINDEX('.', REVERSE(@num))

    RETURN

    CASE WHEN PATINDEX('%[^0-9.-]%', @num) = 0

          AND @num NOT IN ('.', '-', '+', '^')

          AND LEN(@num)>0

          AND @num NOT LIKE '%-%'

          AND (((@pos = LEN(@num)+1)

           OR @pos = CHARINDEX('.', @num)))

         THEN 1

         ELSE 0

    END

END

GO  

However, I think it is a lot easier and powder if we just install RegEx CLR and use it to check for numeric pattern.