expected output from log of negative number

[E. Joshua Rigler]

I understand the theory (at least I did once upon a time, early on in 
graduate school), but I suppose I haven't really needed to apply it 
until recently.  More likely, I just became adept at finding excuses to 
avoid dealing with complex numbers for anything more sophisticated than 
simple 2D fluid flows.  Many thanks to everyone who took time to try to 
(re)educate me.

-EJR

Doug Stewart wrote:
> E. Joshua Rigler wrote:
>> If I type log10(-1), I get a complex number back whose real part is 
>> the log of the absolute value of the argument, and whose imaginary 
>> part is always equal to 1.36438.  What's more, I get similar behavior 
>> with a natural log, but the imaginary part is always equal to Pi.
>>
>> I've managed to confirm that this behavior is compatible with ML, so I 
>> imagine it's not a bug, but can someone explain to me the logic here?
>> _______________________________________________
>> Help-octave mailing list
>> Help-octave at octave.org
>> https://www.cae.wisc.edu/mailman/listinfo/help-octave
>>
>>   
> http://www.newton.dep.anl.gov/askasci/math99/math99180.htm
> 
> Is this good enough or do you want more?