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*Subject*: **Re: [office-formula] FACT/FACTDOUBLE with fractions**

*From*:**"David A. Wheeler" <dwheeler@dwheeler.com>***To*: aguelzow@math.concordia.ab.ca*Date*: Sat, 27 Jan 2007 18:01:54 -0500 (EST)

> > FACT and FACTDOUBLE have > > > > | TBD: Should we mandate that it compute INT() first? Excel 2002 computes > > | the INT() of the parameter first, and then computes the factorial. It'd > > | be more flexible if we allowed fractional values. This has been reworded > > | to note that it's only REQUIRED to support integer parameters, and then > > | permitting GAMMA() for fractional values. > > > > For interoperability we should not allow fractionals. Opinions? Sortof agree. For interoperability, I think we should require INT be applied to the operation first. I believe most applications do that. If you don't want INT applied, use GAMMA. > > Btw, which applications do support GAMMA? > > Gnumeric implements GAMMALN, the natural logarithm of the Gamma > function. So if GAMMA would be defined in OpenFormula we would have > GAMMA in short order. GAMMA is already in OpenFormula. I don't recall if that's in an existing spreadsheet application, but it's obviously a standard and widely-known mathematical function, and it's essentially a universally-defined operation in computer algebra and mathematical systems (Maxima, Octave, etc.). It's also pretty trivial to implement (e.g., if you already have GAMMALN). As long as there is a GAMMA, then we can say that "FACT always does an INT first" without anyone being able to complain that we've lost capability. --- David A. Wheeler

**References**:**FACT/FACTDOUBLE with fractions***From:*Eike Rathke <erack@sun.com>

**Re: [office-formula] FACT/FACTDOUBLE with fractions***From:*"Andreas J. Guelzow" <aguelzow@math.concordia.ab.ca>