Subject: re: Name for new banded matrix structure

From: [email-masked] (Bob Ward)
Date: Wed, 31 May 95 21:33:25 CDT

All -

I have looked in several books on matrix topics and find that there are 
two names used for matrices structured as this one turns out.  One is the 
bordered block banded form Eric mentioned, and one is augmented banded.  
In either case what we end up here is a slightly degenerate form of the 
real thing, but it would seem to work in practice for what we want to 
accomplish by it.  It would not be used in the stated form for 
computation, but must be transformed by the paerser to a "more correct" 
form for computation in any case.

But one question occurs to me ... would it not make the parse a little 
simpler if the entries were augmented into the first rows rather than the 
last, to avoid having to reverse the subscripts when placing the values? 
 What I am afraid of is another situation like the Vdd relative pullup IV 
table, correct but confusing, especially to newcomers to ibis.  I can 
make the argument that there is a special case to be handled in either 
case, but the first row approach seems more like seeing what you get.

All the best,

Bob Ward                [email-masked]