[comp.arch] Array representation and language dependencies

andrew@frip.gwd.tek.com (Andrew Klossner) (03/03/88)

[]
	"There is nothing language dependant about row vector
	representation of 2-d arrays.  It is an implementation tool ..."

Not so.  The Fortran EQUIVALENCE statement lets the programmer overlay
data onto an array.  To make this work, the Fortran standards specify
that arrays must be stored in contiguous memory in column-major order.

  -=- Andrew Klossner   (decvax!tektronix!tekecs!andrew)       [UUCP]
                        (andrew%tekecs.tek.com@relay.cs.net)   [ARPA]

fpst@hubcap.UUCP (Steve Stevenson) (03/03/88)

in article <9812@tekecs.TEK.COM>, andrew@frip.gwd.tek.com (Andrew Klossner) says:
> 
> Not so.  The Fortran EQUIVALENCE statement lets the programmer overlay
> data onto an array.  To make this work, the Fortran standards specify
> that arrays must be stored in contiguous memory in column-major order.

That's only part of the reason.  The initial reason that column major
is used is that in real live linear algebra, a matrix is consider as
column oriented.  That is, unless otherwise specified a 2-d matrix
is a sequence of columns.  EQUIVALENCE came later.

-- 
Steve Stevenson                            fpst@hubcap.clemson.edu
(aka D. E. Stevenson),                     fpst@clemson.csnet
Department of Computer Science,            comp.hypercube
Clemson University, Clemson, SC 29634-1906 (803)656-5880.mabell