Newsgroups: comp.lang.apl
Path: watmath!watserv2.uwaterloo.ca!torn!utcsri!geac!itcyyz!yrloc!rbe
From: rbe@yrloc.ipsa.reuter.COM (Robert Bernecky)
Subject: John Heckman and scans in APL
Message-ID: <1993Feb8.234454.2638@yrloc.ipsa.reuter.COM>
Keywords: scan, Heckman, archaeology 
Reply-To: rbe@yrloc.ipsa.reuter.COM (Robert Bernecky)
Organization: Snake Island Rsearch Inc, Toronto
Date: Mon, 8 Feb 93 23:44:54 GMT

I am trying to track down John Heckman, who wrote the first scan 
functions in APL at least 20-some years ago. 

The Heckman scans, for those of you who only are familiar with the
adverb "\" form, were user-defined functions for performing prefix
and suffix scans of the more common arithmetic and Boolean functions.

They were quite clever in that they only made 2 log N iterations on
the argument.

If nobody know where to contact him, I'm willing to accept a consolation
prize: I want to know when they were created, what the earliest known
citation of them is, and any other information about them.

Thanks. 
Bob
 


Robert Bernecky      rbe@yrloc.ipsa.reuter.com  bernecky@itrchq.itrc.on.ca 
Snake Island Research Inc  (416) 368-6944   FAX: (416) 360-4694 
18 Fifth Street, Ward's Island
Toronto, Ontario M5J 2B9 
Canada
