commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From tobr...@transolutions.net (O'brien, Tim)
Subject Re: [math] exceptions or NaN from Univariate
Date Tue, 13 May 2003 23:42:17 GMT
On Tue, 2003-05-13 at 23:13, Phil Steitz wrote:
<snip/>

> On second thought, I agree with you.  You are correct that if we really 
> want to throw something for "insufficient data" situations, we should 
> require n >= 1 for the mean and either force n >= 2 for variance, std 
> dev or modify these to return 0 if n < 2.  May not be worth the trouble.

I think NaN is a good answer for unanswerable questions like "What is
the mean of an empty set?" or "What is the length of a point?"  Nothing
prevents you from asking the question, and throwing an exception just
seems unnecessary.

Modifying variance and standard deviation to return 0 when n = 1 makes
sense.  

Tim

> 
> Phil
> > 
> > 
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
> > For additional commands, e-mail: commons-dev-help@jakarta.apache.org
> > 
> 
> 
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
> For additional commands, e-mail: commons-dev-help@jakarta.apache.org
> 



---------------------------------------------------------------------
To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
For additional commands, e-mail: commons-dev-help@jakarta.apache.org


Mime
View raw message