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Re: AW: AW: Several comments

This page is part of the web mail archives of SRFI 43 from before July 7th, 2015. The new archives for SRFI 43 contain all messages, not just those from before July 7th, 2015.

"Michael Burschik" <Burschik@xxxxxxxxxxxxxxx> writes:

> > > But my point that an empty vector is a pathological case
> > remains valid.
> > > An empty list, or an empty collection/set, however, is
> > perfectly legitimate.
> >
> > There is nothing more pathological about an empty vector than any of
> > the others.
> I seem to recall that zero-dimensional vectors were considered something of
> an oddity in my algebra classes, and I am pretty certain that I have never
> used one, whereas I use empty lists and empty sets on a regular basis, but
> maybe you are right.

They are like the empty set: they seem odd only until they seem second
nature, at which point they are ordinary and boring.  Rather like
zero, actually.

What is slightly odder is a matrix of dimension zero; such a matrix
necessarily has no elements.  This is unusual, because for any other
dimension, a single-element matrix is possible.  That means that you
can convert scalars to matrixes for any dimension but zero.

Still, not a big deal.