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blah wrote: August 6th, 2021, 10:08 pm I don't know for sure if a CA search DSL would be a good idea in practice or if anyone would use it. But I feel compelled to make this post because I just can't shake the feeling that so many problems like the ones I've mentioned really should be one line. Don't you agree?

Any thoughts?

dvgrn wrote: August 7th, 2021, 8:56 am ...
The closest thing available at the moment might be Mathematica (Wolfram Language), which I think can already handle quite a few of the above problems in one line or a few lines. Can anyone who is more familiar with Mathematica chime in on what its abilities and limitations might be in this context? Might it be relatively easy to write functions to extend Mathematica's abilities to include common tasks like censusing?

dvgrn wrote: August 7th, 2021, 8:56 am The big problem with many of these kinds of problems is not so much that they can't be turned into runnable code. Often the real problem is getting a good estimate of the amount of CPU time or memory resources needed to complete the work -- and in many cases the estimate turns out to be "sometime after the Sun expands as far as Earth's orbit". [...] If it can be done in a way that allows searches to be run and time/resource estimates to be generated in the process, then it will definitely be very useful.

--[[ grammar:
program = iterator '|' selector
iterator = statement*
statement = number 'x' number
statement = '(' number ',' number ')'
statement = 'o'
selector = criterion*
criterion = 'pop' {'>'|'='} number
]]
local g=golly()
local program = g.getstring("Enter your CADSL program.\n"..
"NOTE THAT THIS IS A PROOF OF CONCEPT; NOTHING IS FINAL.")

----------------------------------------------------------------------- ITERATOR
-- All the code in this section deals with candidate pattern generation.

function resetCursor()
	cursorX, cursorY = 0, 0
end

function newPattern()
	resetCursor()
	g.new("")
end

-- STATEMENTS:
function soup(x, y)
	g.select{cursorX, cursorY, x, y}
	g.randfill(50)
	cursorX = cursorX + math.floor(x)
end
function go(x, y)
	cursorX = x
	cursorY = y
end
function dot()
	g.setcell(cursorX, cursorY, 1)
	cursorX = cursorX + 1
end

function doStatement(s)
	-- figure out which kind of statement it is and run it
	local _, _, num1, num2 = s:find("^(%d+)x(%d+)$")
	if _ then soup(num1, num2) end
	_, _, num1, num2 = s:find("^%((%-?%d+),(%-?%d+)%)$")
	if _ then go(num1, num2) end
	if s == "o" then dot() end
end

function doIterator(s)
	for statement in s:gmatch("[^ \t\n;]+") do
		doStatement(statement)
	end
end

----------------------------------------------------------------------- SELECTOR
-- All the code in this section deals with detecting valid results.

function doCriterion(s)
	s = s:gsub("pop",g.getpop())
	local _, _, arg1, comparison, arg2 = s:find("(%w+)([>=])(%w+)")
	arg1 = tonumber(arg1)
	arg2 = tonumber(arg2)
	if comparison == ">" then
		return arg1 > arg2
	elseif comparison == "=" then
		return arg1 == arg2
	end
end

function doSelector(s)
	local shouldShow = true
	for criterion in s:gmatch("[^ \t\n&]+") do
		shouldShow = shouldShow and doCriterion(criterion)
	end
	return shouldShow
end

--------------------------------------------------------------------------------

pipe = program:find("|")
iterator = program:sub(1, pipe - 1)
selector = program:sub(pipe + 1)
-- main loop
i = 0
while true do
	i = i + 1
	newPattern()
	doIterator(iterator:gsub("i",i))
	g.select(g.getrect()) g.copy()
	g.run(1000)
	if doSelector(selector) then
		g.new("") g.paste(0,0,"copy")
		g.warn("Result found! :D ("..i.." tested)")
	end
end

x = 20, y = 20, rule = B3/S23
3o$o$2b2o$2bo13$16b3o$16b2obo$17b3o$16bo2bo!

x = 16, y = 16, rule = B3/S23
2b2obo4b2o2bo$o2bo2bo5bob2o$3o2b2ob2ob5o$6b2obobo2bo$2bob4o2bo3bo$4bo
3bobob3o$2bo2bobo2b3obo$bo2b2o3bo2bob2o$2bo3bobo2b2o2bo$ob2o3bob4obo$b
obo2bo2bo2b4o$5o3bo2bo3bo$2b2ob3o2b4obo$5o4bobob3o$4b2o3b2o$o4bob3ob2o
!

dvgrn wrote: August 7th, 2021, 8:56 am The closest thing available at the moment might be Mathematica (Wolfram Language), which I think can already handle quite a few of the above problems in one line or a few lines. Can anyone who is more familiar with Mathematica chime in on what its abilities and limitations might be in this context? Might it be relatively easy to write functions to extend Mathematica's abilities to include common tasks like censusing?

Yoel wrote: August 11th, 2021, 2:20 am Regarding Mathematica, I personally stay away from proprietary software and I'm sure some people on this forum do the same. There are several free/open source implementations of WL, but they all seem to be incomplete or not entirely compatible with the original one. IMHO, WL/Mathematica is a very specific environment not suitable for everyone.

pzq_alex wrote: September 15th, 2021, 4:01 am

Yoel wrote: August 11th, 2021, 2:20 am Regarding Mathematica, I personally stay away from proprietary software and I'm sure some people on this forum do the same. There are several free/open source implementations of WL, but they all seem to be incomplete or not entirely compatible with the original one. IMHO, WL/Mathematica is a very specific environment not suitable for everyone.

Mathematica itself is not free software, but the Wolfram Engine is, and basically it is a command-line GUI-free version equivalent to Mathematica.

tl;dr: Mathematica is free software.

WARNING: Wolfram Engine is protected by copyright law and international treaties. Unauthorized reproduction or distribution may result in severe civil and criminal penalties and will be prosecuted to the maximum extent possible under law.

Audit
----------------------------------------

You will maintain accurate records of Your use of the Free Engine sufficient to show compliance with these Terms and Conditions, and WRI will have the right to audit such records to confirm compliance therewith. Upon written notice of an audit from WRI, You shall respond within ten (10) business days.

This Engine was created, and is maintained, in the State of Illinois, United States of America. WRI makes no claims that the materials contained on the Free Engine are appropriate or may be downloaded outside of the United States. Access to the Engine and the materials therein (including software) may not be legal by certain persons or in certain countries. If You access this Free Engine from outside the United States, that access is made at Your own risk. You are responsible for compliance with the laws of Your jurisdiction.

You will need a valid activation key and password in order
to proceed. Go to http://user.wolfram.com to
register your activation key and obtain the password.

blah wrote: August 9th, 2021, 6:45 pm [...] If you don't know whether a problem is tractable to brute force or not, then the amount of effort it takes to write a Golly script might compel you to not even bother, since you don't know if it'll work anyway. If that burden of effort is reduced, though, and you only need to write a few lines, you're much more likely to try it, and thus more likely to discover something you otherwise wouldn't have. [...]

blah wrote: August 6th, 2021, 10:08 pm [...] Simulate an explosive rule like /2/3 and list the spaceships that occur in the chaos. (debatable) [...]

x = 16, y = 16, rule = /2/3:T60,60
.B2.2A2.2B2.2B.A$2.2A2.2B.AB.AB$.5BAB2.A.B$.B3A3.A.BA$B3.B.AB.B.ABA.A
$.2B3.A4.BA$BAB.2B2.2B2.A2.A$.B2.ABA.AB2A.3A$A.BAB.B3.4B$B3.B3.ABA.B$
2BAB2A2.2BA.B2.B$BA2.2A.B2.B2.AB$2.A.A.B2.2B3.B$6.2AB3.A$.2A.A.BA$.A.
B5.A.B3.A!

x = 16, y = 16, rule = /2/3:T60,60
A2.A.BA2.2A4.B$B.3A5.B3.B$.A.A.A3B2.B.2B$2.B.B2.2A$A5.A.4BAB.B$2BA.A
3.3A3.B$B7.A2.B3.A$2BA2B.B2.B2A.BA$B.A.A4.A2.B2.A$.B.BA.BA.BA2.AB$.B.
A.BA.BA.B.2AB$7.AB5.AB$B.B2.3A2.BA.A.B$3AB4.B2.A.3A$2.A.B.B2.B2.AB.B$
.B.AB3.B.2B2.2A!