[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Unequal results when using element-wise and broadcast
From: |
Sergei Steshenko |
Subject: |
Re: Unequal results when using element-wise and broadcast |
Date: |
Fri, 22 Nov 2013 10:59:27 -0800 (PST) |
>________________________________
> From: Pantxo Diribarne <address@hidden>
>To: address@hidden; Octave Help <address@hidden>; Mike Miller <address@hidden>
>Sent: Friday, November 22, 2013 8:13 PM
>Subject: Re: Unequal results when using element-wise and broadcast
>
>
>Hello,
>
>It also fails for me with current dev version.
>
>The weird thing is that it is due to "tol = 0" instead of "eps". See the
>exerpt (all differences are within eps):
>
>error: ASSERT errors for: assert (C,C3)
>
> Location | Observed | Expected | Reason
> (7) 0.63854 0.63854 Abs err 1.1102e-16 exceeds tol 0
> (11) 0.00091156 0.00091156 Abs err 1.0842e-19 exceeds tol 0
> (13) 0.15896 0.15896 Abs err 2.7756e-17 exceeds tol 0
>
>
>Pantxo
>_______________________________________________
>
>
>
This can be a manifestation of 80 <-> 64 bit x86 FP numbers, and
absence/presence of failure may depend on 32/64 bit machine. AFAIR 64 bit
machines work only with 64 bit FP numbers while on 32 bit machines FP registers
are 80 bit, but data in memory is stored as 64 bit.
Regards,
Sergei.