RE: [Math] Getter methods in Frequency when there is no data

I agree with returning zero for the absolute frequencies.

For the relative frequencies, I would argue for returning NaN as is done in BivariateRegression when there is insufficient data.

Brent Worden

-----Original Message-----
From: Phil Steitz [mailto:[email protected]]
Sent: Wednesday, August 11, 2004 3:45 PM
To: Jakarta Commons Users List
Subject: RE: [Math] Getter methods in Frequency when there is no data


Thanks for reporting this.
 
I agree that getCumFreq should return 0, but the pct and cumPct are more problematic.  One could argue that an IllegalStateException would be more appropriate for these.  If there have been no values added, percentages don't really make sense.  Thoughts?
 
Phil

	-----Original Message----- 
	From: Shing Hing Man [mailto:[email protected]] 
	Sent: Wed 8/11/2004 7:41 AM 
	To: commonMath 
	Cc: 
	Subject: [Math] Getter methods in Frequency when there is no data
	
	

	Hi,
	  I have tested all the getter methods of
	 org.apache.commons.math.stat.univariate.Frequency
	when
	no data has been added. (If anyone is interested, the
	JUnit test file
	is attached.)
	Here is a summary of the result.
	
	Method                   Result
	getCount                 returns 0 (as expected)
	getCumFreq            
	java.util.NoSuchElementException
	getCumPct              
	java.util.NoSuchElementException
	getPct                   returns NaN 
	f.getSumFreq             return 0 (as expected)
	
	
	Is it reasonable to expect all the getter methods to
	return 0, when
	there is no data ?
	
	My  version of org.apache.commons.math  is dated 10th
	August, 2004.
	
	regards,
	Shing
	
	
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