es.
> >>>
> >>>Bill Venables
> >>>CSIRO Laboratories
> >>>PO Box 120, Cleveland, 4163
> >>>AUSTRALIA
> >>>Office Phone (email preferred): +61 7 3826 7251
> >>>Fax (if absolutely necessary): +61 7 3826 7304
> &g
bles
>>> CSIRO Laboratories
>>> PO Box 120, Cleveland, 4163
>>> AUSTRALIA
>>> Office Phone (email preferred): +61 7 3826 7251
>>> Fax (if absolutely necessary): +61 7 3826 7304
>>> Mobile: +61 4 8819 4402
>>> Home
>Mobile: +61 4 8819 4402
> >Home Phone: +61 7 3286 7700
> >mailto:[EMAIL PROTECTED]
> >http://www.cmis.csiro.au/bill.venables/
> >
> >-Original Message-
> >From: [EMAIL PROTECTED]
> >[mailto:[EMAIL PROT
//www.cmis.csiro.au/bill.venables/
>
> -Original Message-
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf Of Andrew Robinson
> Sent: Tuesday, 6 November 2007 3:10 PM
> To: R-Devel
> Subject: [Rd] A suggestion for an amendment to tapply
>
> Dear R-
] A suggestion for an amendment to tapply
Dear R-developers,
when tapply() is invoked on factors that have empty levels, it returns
NA. This behaviour is in accord with the tapply documentation, and is
reasonable in many cases. However, when FUN is sum, it would also
seem reasonable to retur
Dear R-developers,
when tapply() is invoked on factors that have empty levels, it returns
NA. This behaviour is in accord with the tapply documentation, and is
reasonable in many cases. However, when FUN is sum, it would also
seem reasonable to return 0 instead of NA, because "the sum of an
empt
