[Octave-bug-tracker] [bug #40017] bicgstab fails for complex matrices

[Marco Caliari]

URL:
  <http://savannah.gnu.org/bugs/?40017>

                 Summary: bicgstab fails for complex matrices
                 Project: GNU Octave
            Submitted by: caliari
            Submitted on: Fri 13 Sep 2013 07:02:48 AM GMT
                Category: Octave Function
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Incorrect Result
                  Status: None
             Assigned to: None
         Originator Name: 
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 3.6.2
        Operating System: GNU/Linux

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Details:

Dear all,

bicgstab fails for complex matrices, try


A = rand(4)+1i*rand(4);
bicgstab(A,A*ones(4,1))


whose result should be ones(4,1). The problem is in a couple of complex scalar
products (which are not symmetric). I think


rho_1 = res' * rr;


should be changed to


rho_1 = rr' * res;


and 


omega = (t' * s) / (t' * t);


to


omega = (s' * t) / (t' * t);


Cheers,

Marco




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