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Penrose – Create diagrams by typing notation in plain text

penrose.cs.cmu.edu

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Re: Penrose – Create diagrams by typing notation in plain text

#51

Post by hardmath123 »

A lot of replies here are missing the key idea behind Penrose: that the "substance" and "style" of any mathematical diagram are separable. For example, the "substance" of a diagram might be a collection of sets with known subset relationships:

Set A, B, C

IsSubset(B, A)

IsSubset(C, A)

That same substance can then be rendered in many different styles, e.g. as a Venn diagram or as a tree diagram (substance vs. style is a lot like HTML vs. CSS). Importantly, Penrose's vision is that experts will author libraries of domains and styles, and end-users need only express the substance of their diagrams (i.e. the three lines of code above).

The second beautiful idea in Penrose is that diagram generation is expressed as a constrained optimization problem. This lets you easily experiment with layouts by writing constraints and sampling a variety of potential diagrams via stochastic search.

These two ideas set Penrose apart from most other diagram software out there. I really hope it gains wider adoption. Give it a try!

Re: Penrose – Create diagrams by typing notation in plain text

#53

Post by a2800276 »

thrdbndndn wrote: post #42

I failed to see how it is "plain text". The code in all three tabs looks like, well, code to me.

It's plain text in the generally accepted definition [1] of the term. It's not a binary file that requires special software to author. It's possible to read and write the files in a text editor.

"Plain text" does not imply "natural language description", though I can see the term could be confusing.

[1] https://en.m.wikipedia.org/wiki/Plain_text

Re: Penrose – Create diagrams by typing notation in plain text

#54

Post by a2800276 »

BarbaryCoast wrote: post #10

What's wrong with Pic? Been around for decades.

Pic is wonderful! I think what's lacking the most is modern tool integration. It more or less requires troff which is itself somewhat deprecated. I've always thought that extracting pic as standalone tool with ~modern output objects would be a nice project for once I quit being lazy :)

Re: Penrose – Create diagrams by typing notation in plain text

#55

Post by [deleted] »

laserbeam wrote: post #47

I looked at a random example [1], and this needs heavy rework if it needs to work as an example. I'm scared to look at other examples. - The second half of the 900 line style file is commented out code. Ugh. Should I be learning from examples or reviewing code when I read this? - The end if the style file define/replaces coordinates which are not defined in the substance file. Why? Isn't it the point that a substance…

[deleted]

Re: Penrose – Create diagrams by typing notation in plain text

#59

Post by lifthrasiir »

b800h wrote: post #58

Is this actually affiliated with Roger Penrose? Seems extraordinarily rude to use his name otherwise. Was his permission sought? In fact, this may be seen as "passing off" in English law.

You can say the same thing to Haskell, Curry, Ada or (more or less) Python as well.

Re: Penrose – Create diagrams by typing notation in plain text

#60

Post by b800h »

lifthrasiir wrote: post #59
b800h wrote: post #58

Is this actually affiliated with Roger Penrose? Seems extraordinarily rude to use his name otherwise. Was his permission sought? In fact, this may be seen as "passing off" in English law.

You can say the same thing to Haskell, Curry, Ada or (more or less) Python as well.

Neither Ada Lovelace nor Haskell Curry is still alive. And Python is in a different category.

It's one thing to use the name of a historical figure, quite another to use the recognisable mark of a living person.

Of course, it could all be being done with endorsement, in which case, my comment is invalid, but otherwise it's incredibly rude and a borderline civil tort.

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