Bug 28562 - Incorrect System.Numerics.Complex.Pow(Complex v, Complex p) result
Summary: Incorrect System.Numerics.Complex.Pow(Complex v, Complex p) result
Status: RESOLVED FIXED
Alias: None
Product: Class Libraries
Classification: Mono
Component: General ()
Version: 3.10.0
Hardware: PC Windows
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2015-03-30 14:49 UTC by nader
Modified: 2015-03-31 04:56 UTC (History)
3 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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Status:
RESOLVED FIXED

Description nader 2015-03-30 14:49:58 UTC
It appears that in Xamarin Android and mono 3.3.0 the System.Numerics.Complex.Pow(Complex v, Complex p) returns the wrong result when v is zero. Exponents of zero, when the power is a positive number, should be zero. However this doesn't appear to be the case in Xamarin Android and mono 3.3.0 As the resulting value is NAN.

To reproduce this issue, run the following code snippet
System.Numerics.Complex v = new Complex(0, 0);
System.Numerics.Complex p = new Complex(2, 0);
System.Numerics.Complex r = System.Numerics.Complex.Pow(v, p);

Expected result: r=(0,0)
Xamarin Android result: r=(NAN,NAN)

It should be noted that when running the same code snippet on Windows Phone 8.1, The result is zero, which matches the expected result.
 
The code snippet above was ran using Xamarin Android and Windows Phone 8.1. The same issue
happens when running the code in .Net 4.5 and  mono 3.3.0.

Additional Build Environment info:
Xamarin.Android Version: 4.16.0 (Business Edition)
Java SDK: C:\Program Files (x86)\Java\jdk1.6.0_39
Comment 1 Marek Safar 2015-03-31 04:56:04 UTC
Already fixed in Mono 4.0