ODFF: RATE / spec for omitted parameters

Hi Eike

Briefly looked at RATE this morning. My starting point was:
RATE( Number Nper ; [Number Payment] ; Number Pv ; 
      [ Number Fv = 0 ] ; [ Number PayType = 0 ] 
      [ ; Number Guess = 0.1 ] )

and I planned to add further [] brackets to cope with omitted 
semicolons.

However it looks as if we need to consider exactly what is to be 
legal. Here's a review,  of {Fv; PayType; Guess}, ignoring any 
omitted Payment:

all parameters:
RATE( NPER; Payment; Pv; Fv; PayType; Guess)

missing one parameter:
RATE( NPER; Payment; Pv;   ; PayType; Guess)
RATE( NPER; Payment; Pv; Fv;        ; Guess)
RATE( NPER; Payment; Pv; Fv; PayType       )
RATE( NPER; Payment; Pv; Fv; PayType;      )  Error in Calc; OK 
in Excel

missing two parameters:
RATE( NPER; Payment; Pv;   ;        ; Guess)
RATE( NPER; Payment; Pv;   ; PayType       )
RATE( NPER; Payment; Pv;   ; PayType;      )  Error in Calc; OK 
in Excel
RATE( NPER; Payment; Pv; Fv;        ;      )  Error in Calc; OK 
in Excel
RATE( NPER; Payment; Pv; Fv;               )  Error in Calc; OK 
in Excel
RATE( NPER; Payment; Pv; Fv                )

missing three parameters:
RATE( NPER; Payment; Pv;   ;        ;      )  Error in Calc; OK 
in Excel
RATE( NPER; Payment; Pv;   ;               )  Error in Calc; OK 
in Excel
RATE( NPER; Payment; Pv;                   )  Error in Calc; OK 
in Excel
RATE( NPER; Payment; Pv                    )

I don't have Gnumeric, etc. to hand....

David