[kepler-dev] How do I create nested loops in Kepler

[Edward A. Lee]

Thanks to Mary Stewart, this paper is now on the web:

http://ptolemy.eecs.berkeley.edu/publications/papers/88/recurrencesVLSI-III/

Edward

At 06:01 PM 7/7/2005 +0200, Bertram Ludaescher wrote:

>Edward:
>
>This is very interesting and I'd like to get a hold of it.
>Maybe one of your students could scan it and creat a PDF version!?
>
>Also, in reply to Dan's comment:
>
>  > >I've tried various ways using Ramp actors and Composite actors but
>  > >cannot seem to get this simple case to work.
>
>I guess that this is not as simple a case as one might wish (in simple
>dataflow and/or block diagram languages).. just like doing procedural
>loops in functional or logic programming is tricky (and one has to use
>recursive patterns instead)
>
>Probably Edward's paper will be very instructive in dealing with these
>issues. Also, I think there are nice new opportunities for doing
>procedural stuff nicely in Kepler by using Ptolemy's state machines...
>
>Bertram
>
>
>
>
>Edward A. Lee writes:
>  >
>  > Dan:
>  >
>  > This is a very good question. In fact, I wrote a paper once on this
>  > subject:
>  >
>  > E. A. Lee, "Recurrences, Iteration, and Conditionals in Statically
>  > Scheduled Block Diagram Languages," in VLSI Signal Processing III,
>  > Ed. R. W. Brodersen and H. S. Moscovitz, IEEE Press, New York, 1988.
>  >
>  > This paper is not on the web, although I could get you a copy if you 
> like...
>  >
>  > For your example, the attached model illustrates one simple technique.
>  > It also elaborates on it, producing the iteration indices for both
>  > the outer an inner iterations. There are also much more elaborate
>  > models one can create using higher-order components, like the
>  > IterateOverArray actor and many others that we haven't gotten
>  > around to porting from Ptolemy Classic...
>  >
>  > Edward
>  >
>  >
>  >
>  > At 03:58 PM 7/5/2005 -0700, Dan Higgins wrote:
>  > >Hi All,
>  > >
>  > >     I am having great difficulty in figuring out how to handle various
>  > >looping constructs in Kepler/Ptolemy. So I ask if someone can explain
>  > >how to handle nested loops (using SDF and/or PN directors)?
>  > >
>  > >     For example, assume I want to count from 0 to 3 twice in a row so
>  > >that the output on a final text display is
>  > >0
>  > >1
>  > >2
>  > >0
>  > >1
>  > >2
>  > >
>  > >I've tried various ways using Ramp actors and Composite actors but
>  > >cannot seem to get this simple case to work.
>  > >
>  > >Thanks,
>  > >Dan
>  > >
>  > >--
>  > >*******************************************************************
>  > >Dan Higgins                                  higgins at nceas.ucsb.edu
>  > >http://www.nceas.ucsb.edu/    Ph: 805-893-5127
>  > >National Center for Ecological Analysis and Synthesis (NCEAS)
>  > >Marine Science Building - Room 3405
>  > >Santa Barbara, CA 93195
>  > >*******************************************************************
>  > >
>  > >_______________________________________________
>  > >Kepler-dev mailing list
>  > >Kepler-dev at ecoinformatics.org
>  > >http://mercury.nceas.ucsb.edu/ecoinformatics/mailman/listinfo/kepler-dev
>  >
>  > ------------
>  > Edward A. Lee
>  > Professor, Chair of the EE Division, Associate Chair of EECS
>  > 231 Cory Hall, UC Berkeley, Berkeley, CA 94720
>  > phone: 510-642-0253 or 510-642-0455, fax: 510-642-2845
>  > eal at eecs.Berkeley.EDU, 
> http://ptolemy.eecs.berkeley.edu/~eal 
> _______________________________________________
>  > Kepler-dev mailing list
>  > Kepler-dev at ecoinformatics.org
>  > http://mercury.nceas.ucsb.edu/ecoinformatics/mailman/listinfo/kepler-dev

------------
Edward A. Lee
Professor, Chair of the EE Division, Associate Chair of EECS
231 Cory Hall, UC Berkeley, Berkeley, CA 94720
phone: 510-642-0253 or 510-642-0455, fax: 510-642-2845
eal at eecs.Berkeley.EDU, http://ptolemy.eecs.berkeley.edu/~eal