From bug-octave-request at bevo dot che dot wisc dot edu  Fri Aug 27 00:59:36 1999
Subject: Vector multiplication with complex coefficients giving wrong answer
From: "John W. Eaton" <jwe at bevo dot che dot wisc dot edu>
To: Duncan Barclay <dmlb at ragnet dot demon dot co dot uk>
Cc: bug-octave at bevo dot che dot wisc dot edu, dmlb@computer.my.domain,         dmlb@symbionics.co.uk
Date: Fri, 27 Aug 1999 00:59:50 -0500 (CDT)

On 27-Aug-1999, Duncan Barclay <dmlb at ragnet dot demon dot co dot uk> wrote:

| To: bug-octave at bevo dot che dot wisc dot edu
| Cc: dmlb, dmlb at symbionics dot co dot uk
| Subject: Vector multiplication with complex coefficients giving wrong answer
| 
| Bug report for Octave 2.0.14 configured for i386-unknown-freebsd3.1
| 
| Description:
| -----------
| 
| %
| % Possible bug in matrix multiplation routines when elements are complex.
| %
| % Vectors A and sn are obtained from performing an inverse laplace
| % transform on the transfer function of an electronic circuit. sn are
| % the exponential cofficnts and A contains the constant multpliers.
| %
| %		output = A' * exp(sn * t)
| %
| % gives a different answer to:
| %
| %		for ii = 1:length(A)
| %			output = output + A(ii) * exp(sn(ii) * t)
| %		end;
| %
| % when A has complex elements. If A is real, they give the same answer.

I don't think this is a bug in Octave.

By using the ' operator, you are asking for the complex-conjugate
transpose.

If you just want to change the orientation of the vector, use the .'
operator instead.

jwe



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