Re: ublas : size1 <-> nrows

From: jhrwalter (walter_at_[hidden])
Date: 2002-01-24 05:40:37

--- In boost_at_y..., Jeremy Siek <jsiek_at_c...> wrote:
> 
> It is not important for the matrix dimension functions and the
> multidimensional array dimension functions to have the same names, 
because
> they are different abstractions. There have been many posts in the 
past,
> by myself and other, about why matricies and arrays, though 
agonizingly
> similar in representation, and really very different entities
> mathematically, and should be treated differently in software (with 
which
> we hope to model the mathematics).

May be that's correct for matrices and multidimensional arrays. But 
I'm not sure, if the same holds for matrices and tensors.
 
> If you think of a matrix as a linear operator (which I hope is what 
we are
> aiming for with a linear algebra library), the number of columns is 
the
> dimension of the range, and the number of rows is the dimension of 
the
> domain. Half jokingly, I think domain_size() and range_size() would 
be
> better names than number of rows and columns. 
 
Interesting idea, but I'm not sure, if this is ok for left 
multiplication with a vector.
 
> However, the common usage is
> the field is "number of rows" and "number of columns". If you don't 
name
> the functions accordingly, you'll be forever answering emails about 
what
> "size1" means.

Good point. 
 
It seems to me, that the intermediate results of our (inofficial) 
poll are:
nrows/ncols: 2
size1/size2: ?
 
So let me ask the question the other way round: are there any 
objections, if we rename size1()/size2() to row_count()/column_count
(), index1()/index2() to row_index()/column_index() and iterator1
()/iterator2() to row_iterator()/column_iterator()?
 
Regards
 
Joerg