Re: [NTG-context] supp-ran.lua makes code unable to work in ConTeXt
If you or anyone else is going to play around with generating mazes, definitely take a look at http://www.mazesforprogrammers.com/ and the live demos here: https://weblog.jamisbuck.org/2011/2/7/maze-generation-algorithm-recap A nice overview of the relationship with spanning tress (by the same author) http://www.jamisbuck.org/presentations/rubyconf2011/index.html And another set of visualizations https://bost.ocks.org/mike/algorithms/#maze-generation Aditya ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___
Re: [NTG-context] supp-ran.lua makes code unable to work in ConTeXt
On Sat, 2 May 2020, Hans Hagen wrote:
On 5/1/2020 11:38 PM, Aditya Mahajan wrote:
On Fri, 1 May 2020, Hans Hagen wrote:
On 5/1/2020 6:12 AM, Jairo A. del Rio wrote:
I've adapted the following code to make mazes in LuaLaTeX and ConTeXt:
https://www.rosettacode.org/wiki/Maze_generation#Lua
I defined a modified version to make content visible to TeX and I saved
in a file named maze.lua:
function make_maze_tex(w, h, m)
w = w or 16
h = h or 8
local map = initialize_grid(w*2+1, h*2+1)
function walk(x, y)
map[y][x] = false
local d = { 1, 2, 3, 4 }
shuffle(d)
for i, dirnum in ipairs(d) do
local xx = x + dirs[dirnum].x
local yy = y + dirs[dirnum].y
if map[yy] and map[yy][xx] then
map[avg(y, yy)][avg(x, xx)] = false
walk(xx, yy)
end
end
end
walk(math.random(1, w)*2, math.random(1, h)*2)
...ext/tex/texmf-context/tex/context/base/mkiv/supp-ran.lua:30: C stack
overflow Why does it happen? I guess it has something to do with
math.randomseed, but I don't know how to avoid this error message.
no, it's just lua running out of stack space so it depends on the binary
(and als the initial random value)
But why is it running out of stack? Isn't the walk function tail
recursive, in which case it should not cause a stack overflow
(https://www.lua.org/pil/6.3.html).
not really tail recursive: that is only true when it's the last action and
return is used and it nests very deep
function foo(...)
...
return foo(...)
end
versus
function foo(...)
...
if something then
foo(...)
end
end
Thanks for the clarification.
If you or anyone else is going to play around with generating mazes,
definitely take a look at http://www.mazesforprogrammers.com/
and the live demos here:
https://weblog.jamisbuck.org/2011/2/7/maze-generation-algorithm-recap
Aditya___
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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archive : https://bitbucket.org/phg/context-mirror/commits/
wiki : http://contextgarden.net
___
Re: [NTG-context] supp-ran.lua makes code unable to work in ConTeXt
On 5/1/2020 11:38 PM, Aditya Mahajan wrote:
On Fri, 1 May 2020, Hans Hagen wrote:
On 5/1/2020 6:12 AM, Jairo A. del Rio wrote:
I've adapted the following code to make mazes in LuaLaTeX and
ConTeXt: https://www.rosettacode.org/wiki/Maze_generation#Lua
I defined a modified version to make content visible to TeX and I
saved in a file named maze.lua:
function make_maze_tex(w, h, m)
w = w or 16
h = h or 8
local map = initialize_grid(w*2+1, h*2+1)
function walk(x, y)
map[y][x] = false
local d = { 1, 2, 3, 4 }
shuffle(d)
for i, dirnum in ipairs(d) do
local xx = x + dirs[dirnum].x
local yy = y + dirs[dirnum].y
if map[yy] and map[yy][xx] then
map[avg(y, yy)][avg(x, xx)] = false
walk(xx, yy)
end
end
end
walk(math.random(1, w)*2, math.random(1, h)*2)
...ext/tex/texmf-context/tex/context/base/mkiv/supp-ran.lua:30: C
stack overflow Why does it happen? I guess it has something to do
with math.randomseed, but I don't know how to avoid this error message.
no, it's just lua running out of stack space so it depends on the
binary (and als the initial random value)
But why is it running out of stack? Isn't the walk function tail
recursive, in which case it should not cause a stack overflow
(https://www.lua.org/pil/6.3.html).
not really tail recursive: that is only true when it's the last action
and return is used and it nests very deep
function foo(...)
...
return foo(...)
end
versus
function foo(...)
...
if something then
foo(...)
end
end
Hans
-
Hans Hagen | PRAGMA ADE
Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-
___
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl / http://context.aanhet.net
archive : https://bitbucket.org/phg/context-mirror/commits/
wiki : http://contextgarden.net
___
Re: [NTG-context] supp-ran.lua makes code unable to work in ConTeXt
On Fri, 1 May 2020, Hans Hagen wrote:
On 5/1/2020 6:12 AM, Jairo A. del Rio wrote:
I've adapted the following code to make mazes in LuaLaTeX and ConTeXt:
https://www.rosettacode.org/wiki/Maze_generation#Lua
I defined a modified version to make content visible to TeX and I saved in
a file named maze.lua:
function make_maze_tex(w, h, m)
w = w or 16
h = h or 8
local map = initialize_grid(w*2+1, h*2+1)
function walk(x, y)
map[y][x] = false
local d = { 1, 2, 3, 4 }
shuffle(d)
for i, dirnum in ipairs(d) do
local xx = x + dirs[dirnum].x
local yy = y + dirs[dirnum].y
if map[yy] and map[yy][xx] then
map[avg(y, yy)][avg(x, xx)] = false
walk(xx, yy)
end
end
end
walk(math.random(1, w)*2, math.random(1, h)*2)
...ext/tex/texmf-context/tex/context/base/mkiv/supp-ran.lua:30: C stack
overflow
Why does it happen? I guess it has something to do with math.randomseed,
but I don't know how to avoid this error message.
no, it's just lua running out of stack space so it depends on the binary
(and als the initial random value)
But why is it running out of stack? Isn't the walk function tail recursive, in
which case it should not cause a stack overflow
(https://www.lua.org/pil/6.3.html).
Aditya___
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl / http://context.aanhet.net
archive : https://bitbucket.org/phg/context-mirror/commits/
wiki : http://contextgarden.net
___
Re: [NTG-context] supp-ran.lua makes code unable to work in ConTeXt
On 5/1/2020 6:12 AM, Jairo A. del Rio wrote:
I've adapted the following code to make mazes in LuaLaTeX and ConTeXt:
https://www.rosettacode.org/wiki/Maze_generation#Lua
I defined a modified version to make content visible to TeX and I saved
in a file named maze.lua:
function make_maze_tex(w, h, m)
w = w or 16
h = h or 8
local map = initialize_grid(w*2+1, h*2+1)
function walk(x, y)
map[y][x] = false
local d = { 1, 2, 3, 4 }
shuffle(d)
for i, dirnum in ipairs(d) do
local xx = x + dirs[dirnum].x
local yy = y + dirs[dirnum].y
if map[yy] and map[yy][xx] then
map[avg(y, yy)][avg(x, xx)] = false
walk(xx, yy)
end
end
end
walk(math.random(1, w)*2, math.random(1, h)*2)
tex.print([[\bgroup]])
tex.print([[\baselineskip ]]..m)
local s = {}
for i = 1, h*2+1 do
--table.insert(s, [[\hbox{]])
tex.print([[\hbox{]])
for j = 1, w*2+1 do
-- table.insert(s, [[\hbox{]])
if (j == 1 and i == 2) or (j == 2*w + 1 and i == 2*h) then
tex.print([[\hskip ]]..m)
elseif map[i][j] then
--table.insert(s, [[\vrule width ]]..m..[[ height ]]..m)
tex.print([[\vrule width ]]..m..[[ height ]]..m)
else
--table.insert(s, [[\hskip ]]..m)
tex.print([[\hskip ]]..m)
end
-- table.insert(s, [[}]].."\n")
end
--table.insert(s, [[}]])
tex.print([[}]])
end
--tex.print(table.concat(s))
tex.print([[\egroup]])
end
And I executed the folowing in LuaLaTeX and ConTeXt:
%\documentclass{article}
%\usepackage{luacode}
%\begin{document}
\starttext
%\begin{luacode*}
\startluacode
mz = dofile("maze.lua")
local count = 0
for i=10,109 do
count = count + 1
tex.print([[\subject{Laberinto ]]..count..[[}]])
mz.make_maze_tex(i, i, [[\dimexpr\textwidth/]]..(2*i+1)..[[\relax]])
tex.print([[\pagebreak]])
end
%\end{luacode*}
\stopluacode
%\end{document}
\stoptext
Whereas it works very fast in LuaLaTeX it crashes on ConTeXt and outputs
the following:
btw, fast is relative ... no problem making the code twice as fast
it is actually a nice example for the cld manual ... attached some
output from a first 'improvement' (that version runs some 50-60% faster
so you have a challenge ... actually, it could be a nice challenge for
others on this list: how to make this one contextish and so, maybe we
should have a challenge every few weeks)
token call, execute:
...ext/tex/texmf-context/tex/context/base/mkiv/supp-ran.lua:30: C stack
overflow
Why does it happen? I guess it has something to do with math.randomseed,
but I don't know how to avoid this error message.
no, it's just lua running out of stack space so it depends on the binary
(and als the initial random value)
luatex 1.13 uses lua 5.3 which has a large stack but depending on the
compiler/linker settings and platform (it's 100 but depending on the
situatation you get a message or crash when that doesn't work out)
luajittex has a limited stack of 8000 so it will also crash
luametatex uses lua 5.4 which uses a bit different stack model and can't
go that high (it has a default of 2000 but i will bnump that to 6000
which still seems to work ok, that way i get upto a 120 maze)
(new lmtx upload later this weekend)
Hans
-
Hans Hagen | PRAGMA ADE
Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-
mazecontext.pdf
Description: Adobe PDF document
___
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___
[NTG-context] supp-ran.lua makes code unable to work in ConTeXt
I've adapted the following code to make mazes in LuaLaTeX and ConTeXt:
https://www.rosettacode.org/wiki/Maze_generation#Lua
I defined a modified version to make content visible to TeX and I saved in
a file named maze.lua:
function make_maze_tex(w, h, m)
w = w or 16
h = h or 8
local map = initialize_grid(w*2+1, h*2+1)
function walk(x, y)
map[y][x] = false
local d = { 1, 2, 3, 4 }
shuffle(d)
for i, dirnum in ipairs(d) do
local xx = x + dirs[dirnum].x
local yy = y + dirs[dirnum].y
if map[yy] and map[yy][xx] then
map[avg(y, yy)][avg(x, xx)] = false
walk(xx, yy)
end
end
end
walk(math.random(1, w)*2, math.random(1, h)*2)
tex.print([[\bgroup]])
tex.print([[\baselineskip ]]..m)
local s = {}
for i = 1, h*2+1 do
--table.insert(s, [[\hbox{]])
tex.print([[\hbox{]])
for j = 1, w*2+1 do
-- table.insert(s, [[\hbox{]])
if (j == 1 and i == 2) or (j == 2*w + 1 and i == 2*h) then
tex.print([[\hskip ]]..m)
elseif map[i][j] then
--table.insert(s, [[\vrule width ]]..m..[[ height ]]..m)
tex.print([[\vrule width ]]..m..[[ height ]]..m)
else
--table.insert(s, [[\hskip ]]..m)
tex.print([[\hskip ]]..m)
end
-- table.insert(s, [[}]].."\n")
end
--table.insert(s, [[}]])
tex.print([[}]])
end
--tex.print(table.concat(s))
tex.print([[\egroup]])
end
And I executed the folowing in LuaLaTeX and ConTeXt:
%\documentclass{article}
%\usepackage{luacode}
%\begin{document}
\starttext
%\begin{luacode*}
\startluacode
mz = dofile("maze.lua")
local count = 0
for i=10,109 do
count = count + 1
tex.print([[\subject{Laberinto ]]..count..[[}]])
mz.make_maze_tex(i, i, [[\dimexpr\textwidth/]]..(2*i+1)..[[\relax]])
tex.print([[\pagebreak]])
end
%\end{luacode*}
\stopluacode
%\end{document}
\stoptext
Whereas it works very fast in LuaLaTeX it crashes on ConTeXt and outputs
the following:
token call, execute:
...ext/tex/texmf-context/tex/context/base/mkiv/supp-ran.lua:30: C stack
overflow
Why does it happen? I guess it has something to do with math.randomseed,
but I don't know how to avoid this error message.
local mazegen = {}
math.randomseed( os.time() )
-- Fisher-Yates shuffle from http://santos.nfshost.com/shuffling.html
local function shuffle(t)
for i = 1, #t - 1 do
local r = math.random(i, #t)
t[i], t[r] = t[r], t[i]
end
end
mazegen.shuffle = shuffle
-- builds a width-by-height grid of trues
local function initialize_grid(w, h)
local a = {}
for i = 1, h do
table.insert(a, {})
for j = 1, w do
table.insert(a[i], true)
end
end
return a
end
mazegen.initialize_grid = initialize_grid
-- average of a and b
local function avg(a, b)
return (a + b) / 2
end
local dirs = {
{x = 0, y = -2}, -- north
{x = 2, y = 0}, -- east
{x = -2, y = 0}, -- west
{x = 0, y = 2}, -- south
}
local function make_maze(w, h)
w = w or 16
h = h or 8
local map = initialize_grid(w*2+1, h*2+1)
function walk(x, y)
map[y][x] = false
local d = { 1, 2, 3, 4 }
shuffle(d)
for i, dirnum in ipairs(d) do
local xx = x + dirs[dirnum].x
local yy = y + dirs[dirnum].y
if map[yy] and map[yy][xx] then
map[avg(y, yy)][avg(x, xx)] = false
walk(xx, yy)
end
end
end
walk(math.random(1, w)*2, math.random(1, h)*2)
local s = {}
for i = 1, h*2+1 do
for j = 1, w*2+1 do
if map[i][j] then
table.insert(s, '#')
else
table.insert(s, ' ')
end
end
table.insert(s, '\n')
end
return table.concat(s)
end
mazegen.make_maze = make_maze
function make_maze_tex(w, h, m)
w = w or 16
h = h or 8
local map = initialize_grid(w*2+1, h*2+1)
function walk(x, y)
map[y][x] = false
local d = { 1, 2, 3, 4 }
shuffle(d)
for i, dirnum in ipairs(d) do
local xx = x + dirs[dirnum].x
local yy = y + dirs[dirnum].y
if map[yy] and map[yy][xx] then
map[avg(y, yy)][avg(x, xx)] = false
walk(xx, yy)
end
end
end
walk(math.random(1, w)*2, math.random(1, h)*2)
tex.print([[\bgroup]])
tex.print([[\baselineskip ]]..m)
local s = {}
for i = 1, h*2+1 do
--table.insert(s, [[\hbox{]])
tex.print([[\hbox{]])
for j = 1, w*2+1 do
-- table.insert(s, [[\hbox{]])
if (j == 1 and i == 2) or (j == 2*w + 1 and i == 2*h) then
tex.print([[\hskip ]]..m)
elseif map[i][j] then
--table.insert(s, [[\vrule width ]]..m..[[ height ]]..m)
tex.print([[\vrule width ]]..m..[[ height ]]..m)
else
--table.insert(s, [[\hskip ]]..m)
tex.print([[\hskip ]]..m)
end
-- table.insert(s, [[}]].."\n")
end
--table.insert(s, [[}]])
tex.print([[}]])
end
--tex.print(table.concat(s))
tex.print([[\egroup]])
end
mazegen.make_maze_tex = make_maze_tex
return mazegen
\starttext
\startluacode
mz = dofile("maze.lua")
local count = 0
for i=10,109 do
