[GRASS5] s.univar + s.windavg + new code = s.cellstats

[Roger Bivand]

On Wed, 18 Sep 2002, Eric G. Miller wrote:

> It came up on the other list about calculating s.univar stats
> for sites in a cell.  I've been going back and forth with Gordon Keith
> on the other list and privately, about a modified s.univar.
> 
> Anyway, I've got most of a version but I hit a snag when the count
> for a cell is one.  Some of the stats come up NaN.  At the moment,
> I've hooked in modifications so the offending stats don't divide
> by zero (which was the problem).  Now, if there's just one data point,
> what are appropriate values for:
> 
>   standard deviation (0.0 ?)
>   skewness (0.0 ?)
>   kurtosis (-3.0?)
>   coefficient of variation (0.0?)