commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Phil Steitz (JIRA)" <j...@apache.org>
Subject [jira] Updated: (MATH-163) The evaluate method and the getResult method of class Variance give different results
Date Sat, 02 Jun 2007 03:27:15 GMT

     [ https://issues.apache.org/jira/browse/MATH-163?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Phil Steitz updated MATH-163:
-----------------------------

    Fix Version/s: 1.2

> The evaluate method and the getResult method of class Variance give different results
> -------------------------------------------------------------------------------------
>
>                 Key: MATH-163
>                 URL: https://issues.apache.org/jira/browse/MATH-163
>             Project: Commons Math
>          Issue Type: Bug
>    Affects Versions: 1.1
>            Reporter: Nele Smeets
>             Fix For: 1.2
>
>
> Consider the following test code:
>   // construct an array of input values, containing infinity  
>   double[] values = new double[] {1.0, 2.0, Double.POSITIVE_INFINITY};
>   // find the variance using Variance.evaluate(double[])
>   Variance var1 = new Variance();
>   double value1 = var1.evaluate(values);
>   // find the variance using Variance.getResult()
>   Variance var2 = new Variance();
>   var2.incrementAll(values);
>   double value2 = var2.getResult();
>   // print out the results
>   System.out.println(value1);
>   System.out.println(value2);
> This code prints out:
> NaN
> Infinity
> So, we get two different variances, depending on the method we use. 
> (The same is true when we use Double.NEGATIVE_INFINITY as input value instead of Double.POSITIVE_INFINITY.)

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


---------------------------------------------------------------------
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