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Re: C++ template

 From: Fredrik Bulow Subject: Re: C++ template Date: Mon, 4 Oct 2004 15:39:12 -0500

```Yes it will.

I've just installed Octave 2.1.57 and now everything works perfect.

On Mon, 2004-10-04 at 19:15, Henry F. Mollet wrote:
> I have an older version of octave (2.1.46) and I get
> octave:2> a(6)==a(1,2)
> error: single index only valid for row or column vector
> error: evaluating binary operator `==' near line 2, column 5
>
> I have to vectorize 'a' first before I can compare a(6) with a(1,2):
> octave:2> b=vec(a);
> octave:5> b(6)==a(1,2)
> ans = 1
>
> Will a newer version of Octave know what to do with a(6) if a is a 5x5
> matrix?
> Henry
>
>
>
> on 10/4/04 5:12 AM, Stefan van der Walt at address@hidden wrote:
>
> > I am not sure what you mean, since all the examples listed under "Linear
> > Indexing" in the document below works as stated.
> >
> > octave:1> a = ones(5,5)
> > a =
> >
> > 1  1  1  1  1
> > 1  1  1  1  1
> > 1  1  1  1  1
> > 1  1  1  1  1
> > 1  1  1  1  1
> >
> > octave:2> a(6)==a(1,2)
> > ans = 1
> >
> > Which compares the 6th element of 'a' to the second in the first row.
> > If you want to compare a(6) to the first two elements, you have to do
> >
> > octave:6> a(6)==a(1:2)
> >
> > or
> >
> > octave:7> a(6)==a([1 2])
> >
> > Regards
> > Stefan
> >
> > On Mon, Oct 04, 2004 at 04:46:22AM -0500, Fredrik Bulow wrote:
> >> hmm....
> >>
> >> Linear indexing (i.e. a(6)==a(1,2) for a 5x5 matrix) does not seem to be
> >> implemented yet. Or can it be turned on in some way? (Linear indexing is
> >> described in the below link.)
> >>
> >> The "find" function seems to be built on the idea that linear indexing
> >> is available since find(eye(5)) does return [1 7 13 19 25]'.
> >>
> >> /Fredrik
> >>
> >> On Mon, 2004-10-04 at 07:19, Paul Thomas wrote:
> >>> Fredrik Bulow wrote:
> >>>
> >>>> Thank you!
> >>>>
> >>>>
> >>> You are more than welcome.
> >>>
> >>>>
> >>>>
> >>> Most octave programmes can be vectorised, although it is not always
> >>> obvious how.  All that applies to Matlab, in this area, applies to
> >>> octave as well.  The following technical note is therefore very useful
> >>> and should be read by all octave/Matlab/Scilab/... users, regardless of
> >>> which they use:
> >>>
> >>> http://www.mathworks.com/support/tech-notes/1100/1109.html
> >>>
> >>> The speedup that can be obtained is often more than that from writing a
> >>> dynamically linked function - especially if the development time of the
> >>> latter is taken into account.
> >>>
> >>> Best regards
> >>>
> >>> Paul T
> >>>
> >>
> >>
> >>
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> >> Octave is freely available under the terms of the GNU GPL.
> >>
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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
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> >
>

-------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

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