inv(): different behavior to matlab?

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inv(): different behavior to matlab?

Michael Taeschner-2

I just installed octave-1.1.1 on linux-1.2.13 and run a matlab-script I
was given. It tries to solve a linear simultanous eq. system by inverting
the matrix like:

Y = inv(Q)*P

Q is obviously of bad condition therefor I get the message:

Warning:inverse: matrix singular to machine precision rcond=3.64473e-22

There is no solution given back and thus no results available. In
contrast matlab for windows (4.0) gives exactly the same rcond and message,
but continues execution and inverts the matrix Q. The result is correct,
as I verified with arbitrary precision arithmetics by MuPAD.

In the beginning of the script is a line:

format long e

Question: What am I doing wrong and how can I make octave behave like
matlab, e.g. continuing calculation?

Michael Taeschner

Student of Engineering Mechanics:
University of Magdeburg: [hidden email]