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Do you have a suggestion on where to / how to start learning Prolog beyond towers-of-hanoi? Prolog is basically the last language on my list of things I want t

by lynx23 2y ago

Do you have a suggestion on where to / how to start learning Prolog beyond towers-of-hanoi? Prolog is basically the last language on my list of things I want to look at, but whenever I tried, I failed to find anything practical to do/try.

dbcurtis 2y ago
Try a rules-based synthesis problem. Prolog style (put simplisticly) is to write down what is true about a solution, and turn the search engine loose. Prolog is still procedural, unfortunately, so practical Prolog requires understanding the search algorithm. A suggestion: produce the XY locations of the nails for a building-code-compliant nailing pattern for a panel of plywood roof sheathing. Allow different stud spacing and wind speed zones. This is a small toy problem but will channel your thought process toward something Prologgy.
- tonyarkles 2y ago
  I love this example so much. I used a similar kind of problem a year or so ago when playing with some kind of logic/linear programming/optimization system: given a set of shelves (width and length), find the set of guillotine cuts (cuts across the entire sheet) that minimizes how many sheets of plywood are needed. If I recall the general problem is actually in NP but by formulating it as a problem of finding a list of operations (new sheet, cut sheet X horizontally, cut sheet X vertically) the solver was able to come up with high quality solutions in seconds. I then took it and added a second level: once it has found a minimal number of sheets, minimize the number of cuts. Super handy little tool! Once I had the solver part figured out and added a little tweak for handling kerf, it was quite simple to have it spit out an SVG that showed all of the pieces and cuts. And now… I want to go find that code and play with it again. Super fun stuff outside of the daily grind.
amock 2y ago
I’ve enjoyed https://www.metalevel.at/prolog https://www.metalevel.at/prolog but I’m not a Prolog Programmer.
- lynx23 2y ago
  Ah, thanks for the link! I know his YouTube channel, but somehow I never realized there is a webpage too!
lordwarnut 2y ago
I have been going through https://www.ic.unicamp.br/~meidanis/courses/mc336/2009s2/prolog/problemas/ https://www.ic.unicamp.br/~meidanis/courses/mc336/2009s2/pro... It starts out pretty easy but gets harder and requires more thought. It has different sections on things like list processing or graph problems.

by lynx23 2y ago

dbcurtis 2y ago

Try a rules-based synthesis problem. Prolog style (put simplisticly) is to write down what is true about a solution, and turn the search engine loose. Prolog is still procedural, unfortunately, so practical Prolog requires understanding the search algorithm. A suggestion: produce the XY locations of the nails for a building-code-compliant nailing pattern for a panel of plywood roof sheathing. Allow different stud spacing and wind speed zones. This is a small toy problem but will channel your thought process toward something Prologgy.

tonyarkles 2y ago
I love this example so much. I used a similar kind of problem a year or so ago when playing with some kind of logic/linear programming/optimization system: given a set of shelves (width and length), find the set of guillotine cuts (cuts across the entire sheet) that minimizes how many sheets of plywood are needed. If I recall the general problem is actually in NP but by formulating it as a problem of finding a list of operations (new sheet, cut sheet X horizontally, cut sheet X vertically) the solver was able to come up with high quality solutions in seconds. I then took it and added a second level: once it has found a minimal number of sheets, minimize the number of cuts. Super handy little tool! Once I had the solver part figured out and added a little tweak for handling kerf, it was quite simple to have it spit out an SVG that showed all of the pieces and cuts. And now… I want to go find that code and play with it again. Super fun stuff outside of the daily grind.

amock 2y ago

I’ve enjoyed https://www.metalevel.at/prolog https://www.metalevel.at/prolog but I’m not a Prolog Programmer.

lynx23 2y ago
Ah, thanks for the link! I know his YouTube channel, but somehow I never realized there is a webpage too!

lordwarnut 2y ago

I have been going through https://www.ic.unicamp.br/~meidanis/courses/mc336/2009s2/prolog/problemas/ https://www.ic.unicamp.br/~meidanis/courses/mc336/2009s2/pro... It starts out pretty easy but gets harder and requires more thought. It has different sections on things like list processing or graph problems.