|
|
Blitz Support : |
From: Alex Fore (agf_at_[hidden])
Date: 2003-07-20 12:41:59
I think what he is trying to say, correct me if I am wrong, is that he would like a way to di this without having to specify all of the range arguments. i.e if we had a rank 3 array, and you wanted to pull out a subarray containing all elements of the array where the firstDimension's index was 5. with slicing one would need to:
Array<T,3> big_array(10,10,10);
Array<T,2> subarray;
subarray = big_array(5,Range::all(),Range::all());
when it would be nice to have a way to do this by just specifying that you want all elements which are indexed by j in the i'th dimension.
int i = 0; int j = 5;
subarray = big_array.sub(i,j);
But the rank of tensor is a template argument so I dunno if this can be done in a rank - independant way.
-Alex
On Sun, 20 Jul 2003 13:22:44 -0400
"Dalal, Navneet" <navneet.dalal_at_[hidden]> wrote:
> Thanks Todd,
>
> but as I want to write meta programmes, so this way of specifying slicing
> will be different for different dimensions.
> I am looking for dimension independent function or operator.
>
> thanks
> navneet
>
> > -----Original Message-----
> > From: Todd Veldhuizen [mailto:tveldhui_at_[hidden]]
> > Sent: Sunday, July 20, 2003 1:14 PM
> > To: Support list for Blitz++
> > Subject: Re: [Blitz-support] Sub arrays in blitz meta programming
> >
> >
> > Hi Navneet,
> >
> > Try simply
> >
> > Array<double,1> b = a(5, Range::all());
> >
> > See the slicing section of the manual for more detail:
> > http://www.oonumerics.org/blitz/manual/blitz02.html#index00087
> >
> > Cheers,
> > Todd
> > --
> > Todd Veldhuizen / tveldhui_at_[hidden] / Indiana University
> > Computer Science
> >
> > On Thu, 17 Jul 2003, Dalal, Navneet wrote:
> >
> > > Hi,
> > >
> > > I am writing bilinear interpolation code using blitz
> > arrays. I would like to
> > > write this code for general N-d arrays using meta programming.
> > >
> > > However, I am stuck with one problem: how can I get a sub
> > array along one
> > > particular dimension for a blitz array ?
> > >
> > > What I need is something like this:
> > >
> > > Array<double, 2> a (10, 10);
> > > // init a
> > >
> > > int index = 5;
> > > int firstDimension = 0;
> > >
> > > Array<double,1> b = a.subarray(firstDimension, index);
> > >
> > > // now b points to a(5, range::all)
> > >
> > >
> > >
> > > Is there a function or operator already overloaded for this purpose?
> > >
> > > thanks
> > > navneet
> > > _______________________________________________
> > > Blitz-support mailing list
> > > Blitz-support_at_[hidden]
> > > http://www.oonumerics.org/mailman/listinfo.cgi/blitz-support
> > >
> > _______________________________________________
> > Blitz-support mailing list
> > Blitz-support_at_[hidden]
> > http://www.oonumerics.org/mailman/listinfo.cgi/blitz-support
> >
> _______________________________________________
> Blitz-support mailing list
> Blitz-support_at_[hidden]
> http://www.oonumerics.org/mailman/listinfo.cgi/blitz-support
>