4 ms·

Stargazer: understanding the π-calculus, visually

91 points by 14113 9y ago

hdhzy 9y ago
Also relevant: Pict [0], a π-calculus programming language. [0]: http://www.cis.upenn.edu/~bcpierce/papers/pict/Html/Pict.html http://www.cis.upenn.edu/~bcpierce/papers/pict/Html/Pict.htm...
amelius 9y ago
Anyone here knows a good self contained description?
- speps 9y ago
  https://en.wikipedia.org/wiki/%CE%A0-calculus https://en.wikipedia.org/wiki/%CE%A0-calculus One of the links from that article : http://www.cs.tufts.edu/~nr/cs257/archive/jeannette-wing/pi.pdf http://www.cs.tufts.edu/~nr/cs257/archive/jeannette-wing/pi....
shaunxcode 9y ago
This is awesome! Does it do anything like fdr or can it be plugged in to play traces demonstrating live/deadlock?
k2xl 9y ago
For those of us who have never heard of pi calculus, can someone give a beginners description (wikipedia article just confused me even more)
- wz1000 9y ago
  The pi-calculus is a mathematical formalization of concurrent programs in the same way that lambda calculus is a formalization of computable functions. It is basically a notation that allows you to easily specify concurrent programs, and then rigorously reason about them.
  - deleted 9y ago
    [deleted]
kuwze 9y ago
There is also the Join calculus in case anyone is interested. [0]: https://en.wikipedia.org/wiki/Join-calculus https://en.wikipedia.org/wiki/Join-calculus
- WorldMaker 9y ago
  In college I was fascinated by the Join calculus, in particular it's research implementation in Polyphonic C# and its successors.
nickpsecurity 9y ago
For those wondering about practical application, here's two quick examples on use with distributed, problem solving and web applications. They're both doing precise models with a focus on deadlock prevention. http://www2.cs.siu.edu/~rahimi/papers/2.pdf http://www2.cs.siu.edu/~rahimi/papers/2.pdf http://www.sersc.org/journals/IJGDC/vol8_no5/13.pdf http://www.sersc.org/journals/IJGDC/vol8_no5/13.pdf
peterlk 9y ago
I love the pi calculus. It's a good starting point for analyzing distributed systems in a rigorous way. If you're interested in learning more about this kind of thing, check out the Kell calculus[0] and it's related calculi [0] http://www-verimag.imag.fr/~bidinger/publi/fmoods2003.pdf http://www-verimag.imag.fr/~bidinger/publi/fmoods2003.pdf
abstrakraft 9y ago
"pi-calculus" would be a better term to use in the title, since the glyph used for pi looks like "n"
- 14113 9y ago
  I just followed the guidelines when submitting - i.e: > Otherwise please use the original title, unless it is misleading or linkbait. It's regrettable that π looks similar to n, however I think it's a very minor issue that is resolved the second that you click the link.
- adrianratnapala 9y ago
  Only if you use terrible fonts.

91 points by 14113 9y ago

Also relevant: Pict [0], a π-calculus programming language. [0]: http://www.cis.upenn.edu/~bcpierce/papers/pict/Html/Pict.html http://www.cis.upenn.edu/~bcpierce/papers/pict/Html/Pict.htm...

amelius 9y ago

Anyone here knows a good self contained description?

speps 9y ago
https://en.wikipedia.org/wiki/%CE%A0-calculus https://en.wikipedia.org/wiki/%CE%A0-calculus One of the links from that article : http://www.cs.tufts.edu/~nr/cs257/archive/jeannette-wing/pi.pdf http://www.cs.tufts.edu/~nr/cs257/archive/jeannette-wing/pi....

shaunxcode 9y ago

This is awesome! Does it do anything like fdr or can it be plugged in to play traces demonstrating live/deadlock?

k2xl 9y ago

For those of us who have never heard of pi calculus, can someone give a beginners description (wikipedia article just confused me even more)

wz1000 9y ago
The pi-calculus is a mathematical formalization of concurrent programs in the same way that lambda calculus is a formalization of computable functions. It is basically a notation that allows you to easily specify concurrent programs, and then rigorously reason about them.
- deleted 9y ago
  [deleted]

kuwze 9y ago

There is also the Join calculus in case anyone is interested. [0]: https://en.wikipedia.org/wiki/Join-calculus https://en.wikipedia.org/wiki/Join-calculus

WorldMaker 9y ago
In college I was fascinated by the Join calculus, in particular it's research implementation in Polyphonic C# and its successors.

nickpsecurity 9y ago

For those wondering about practical application, here's two quick examples on use with distributed, problem solving and web applications. They're both doing precise models with a focus on deadlock prevention. http://www2.cs.siu.edu/~rahimi/papers/2.pdf http://www2.cs.siu.edu/~rahimi/papers/2.pdf http://www.sersc.org/journals/IJGDC/vol8_no5/13.pdf http://www.sersc.org/journals/IJGDC/vol8_no5/13.pdf

peterlk 9y ago

I love the pi calculus. It's a good starting point for analyzing distributed systems in a rigorous way. If you're interested in learning more about this kind of thing, check out the Kell calculus[0] and it's related calculi [0] http://www-verimag.imag.fr/~bidinger/publi/fmoods2003.pdf http://www-verimag.imag.fr/~bidinger/publi/fmoods2003.pdf

abstrakraft 9y ago

"pi-calculus" would be a better term to use in the title, since the glyph used for pi looks like "n"

14113 9y ago
I just followed the guidelines when submitting - i.e: > Otherwise please use the original title, unless it is misleading or linkbait. It's regrettable that π looks similar to n, however I think it's a very minor issue that is resolved the second that you click the link.
adrianratnapala 9y ago
Only if you use terrible fonts.