[Octave-bug-tracker] [bug #65020] Issues with inv() on new intel architecture

[anonymous]

Follow-up Comment #4, bug#65020 (group octave):

On the Xeon system: 
octave:1> randn('seed',0);
octave:2> A = randn(100);
octave:3> B = inv(A);
octave:4> max(max(abs(A*B - eye(100))))
ans = 2.8047e+04

On the AMD system: 
octave:1> randn('seed',0);
octave:2> A = randn(100);
octave:3> B = inv(A);
octave:4> max(max(abs(A*B - eye(100))))
ans = 6.0140e-14

Here is a bit of background. I have written a computational fluid dynamics
code in Octave about 15+ years ago. It has been working well all these years
on various platforms. It contains one matrix inversion; the matrix is
well-conditioned, and I have never had any issues. 

In order to diagnose the root of this problem, I am creating the random number
array. In the actual code, it is not random.  


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