Re: strange problem

[Paul Kienzle]

I'm not a fan of hard-coded constants.  I would use

        x = fix(x/eps)*eps

The following may be more efficient:

        x(abs(x)<eps) = 0

If you prefer relative rather than absolute uncertainty, use:

        x(abs(x)<max(abs(x(:)))*eps) = 0


Paul Kienzle
address@hidden

On Dec 3, 2003, at 5:09 PM, robert Macy wrote:

> I would use something like...
>
> x = fix(x*1e16)/1e16;
>
>              - Robert -
>
>
> On Wed, 03 Dec 2003 13:51:51 -0800
>  "Henry F. Mollet" <address@hidden> wrote:
> > octave:14> x=-0.000000000000000020817
> > x =  -2.0817e-17
> > octave:15> fix(x)
> > ans = 0
> > Henry
> >
> >
> > on 11/27/03 11:58 PM, Christoph Dalitz at
> > address@hidden
> > wrote:
> >
> > > On Thu, 27 Nov 2003 23:03:26 +0000
> > > Geraint Paul Bevan <address@hidden> wrote:
> > > > |
> > > > |    -2.0817e-17    1.0000e+02
> > > > |    -1.0000e-02    1.0000e+00
> > > > |
> > > >
> > > > The number -2.0817e-17 is -0.000000000000000020817,
> > which is very, very
> > > > close to zero.
> > > Is there an Octave function that truncates/rounds such
> > small numbers to
> > > zero (like the Scilab function "clean")?
> > >
> > > I have tried "help round" and "help trunc", but found
> > nothing appropriate.
> > > Thanks,
> > >
> > > Christoph
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Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
Subscription information:  http://www.octave.org/archive.html
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