[MATH-402] Complex.ZERO.pow(Complex.ONE) gives NaN in unit tests

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 1.2, 2.0, 2.1
• Fix Version/s: 2.2

Environment

Issue 15 http://code.google.com/p/symja/issues/detail?id=15

• Assignee: Unassigned
• Reporter: Axel Kramer
• Created: 05/Aug/10 16:39
• Updated: 01/Jan/11 01:26
• Resolved: 01/Jan/11 01:26

Description

Why does this unit test in ComplexTest.java gives NaN?
I expected to get Complex.ZERO as the result?

 
   public void testPowZero() {
       TestUtils.assertSame(Complex.NaN,
               Complex.ZERO.pow(Complex.ONE));
...
   }

I would suggest something like this for the Complex#pow() method:

 
    public Complex pow(Complex x) {
        if (x == null) {
            throw new NullPointerException();
        }
        if (x.imaginary == 0.0) {
          if (real == 0.0 && imaginary == 0.0) {
            if (x.real == 0.0){      	
            	return Complex.ZERO;
            }
          }
          if (x.real == 1.0) {
          	return this;
          }
        }
        return this.log().multiply(x).exp();
    }