Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!cernvax!chx400!cgch!wasc
From: wasc@cgch.uucp (Armin Schweizer)
Newsgroups: comp.software-eng
Subject: Re: CASE tools, esp. Software through Pictures.
Message-ID: <1990Feb9.094852.19778@cgch.uucp>
Date: 9 Feb 90 09:48:52 GMT
References: <1990Feb6.215234.6561@is.uu.no>
Sender: news@cgch.uucp (EUnet/USENET News Agent)
Reply-To: wasc@cgch.UUCP (Armin Schweizer)
Organization: CIBA-GEIGY AG, Basle, Switzerland
Lines: 44

In an earlier project for embedded realtime software (about 2
man years effort) we used the Teamwork-PC tool. This tool
supports data flow diagrams only (no real time extensions 
according to hatley/pirbhai or ward/mellor, no structured
design according to yourdon).

As this happens often, the project was late. So we added
to the two team members a third one (Remember: adding manpower
to a late software project makes it later). Since the
structure of this small piece of software (about 15'000
lines) was very clear, the interfaces well defined and
the interaction between the functions minimal (all effects
of theuse of the SA technique), the additional manpower
was very efficient. The maintenance of the software is,
compared with earlier developments, much easier and less
error prone (remember: in each major release of the OS/360
about 1000 errors were removed, but it was estimated, that
the total number was constant at 5000 errors).

The people reacted first somewhat reluctant (we did it the
good old way for 5 years now, why change?), but already
during the project lifetime they would have shot at everybody
who intended to take away this tool.

Now what can the tool add to the technique? The tools are
(in most cases) not only drawing aids, but provide a lot of
checks and today start even to give automatic support
when moving from analysis to design and coding phases!

I am far away of promising 10 times higher productivity, as others
have done. But the tools have a payback time, which is shorter
than the first projects development time, not to speek of the 
maintenance time of the first project.

It will be a good decision to purchase such a tool.

kind regards
arminius



       Armin R. Schweizer, CIBA-GEIGY AG, R1045.P.06, WRZ
                  4002 Basel / Switzerland
	          phone: -41-61-697'79'46