Eufalesio at 13:36, 11 November 2025

2025-11-11T13:36:35Z

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Eufalesio at 13:27, 11 November 2025

2025-11-11T13:27:30Z

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Eufalesio at 13:20, 11 November 2025

2025-11-11T13:20:15Z

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Eufalesio: Vibe coded v1.1

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Vibe coded v1.1

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Eufalesio: Birth [Vibe coded v1]

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-- Module:ChordVoicings (Scribunto-safe, no // or bitwise ops)
-- Usage via template: {{ChordVoicingTable|rchord=4:5:6:7}}

local p = {}

-- -------- utilities --------
local function split_enum(s)
local t = {}
for num in string.gmatch(s or "", "%d+") do
t[#t+1] = tonumber(num)
end
return t
end

local function gcd(a,b)
while b ~= 0 do a, b = a % b, b end
return math.abs(a)
end
local function gcd_list(t)
local g = t[1]
for i=2,#t do g = gcd(g, t[i]) end
return g
end

local function odd_part(n)
-- remove all factors of 2 using integer division compatible with Lua 5.1
while n % 2 == 0 do n = math.floor(n / 2) end
return n
end

local function copy(t)
local u = {}
for i=1,#t do u[i]=t[i] end
return u
end

local function reduce_irreducible(t)
local g = gcd_list(t)
if g>1 then
local u = {}
for i=1,#t do u[i]=math.floor(t[i]/g) end
return u
end
return copy(t)
end

local function to_str(t)
local parts = {}
for i=1,#t do parts[i]=tostring(t[i]) end
return table.concat(parts, ":")
end

local function sort_key(t)
local parts = {}
for i=1,#t do parts[i]=string.format("%03d", t[i]) end
return table.concat(parts, "-")
end

local function span_ratio(t)
local mn, mx = t[1], t[1]
for i=2,#t do
if t[i]<mn then mn=t[i] end
if t[i]>mx then mx=t[i] end
end
return mx / mn
end

-- rotate across two octaves: move first*4 to end, then reduce
local function rot2_once(t)
local n = #t
local u = {}
for i=2,n do u[#u+1] = t[i] end
u[#u+1] = t[1]*4
return reduce_irreducible(u)
end

local function rotation_for_first_odd(start_vec, target_odd, cap)
local t = reduce_irreducible(start_vec)
for _=1,cap do
local first_odd = odd_part(t[1])
if first_odd == target_odd then return t end
t = rot2_once(t)
end
return t
end

local function toodds(enum)
local odds = {}
for i=1,#enum do odds[i] = odd_part(enum[i]) end
return odds
end

local function unique_in_order(t)
local seen, out = {}, {}
for _,x in ipairs(t) do
if not seen[x] then seen[x]=true; out[#out+1]=x end
end
return out
end

-- generate all non-empty subsets of an array, as arrays themselves
local function all_nonempty_subsets(arr)
local res = {}
local function rec(i, cur)
if i > #arr then
if #cur > 0 then
local add = {}
for k=1,#cur do add[k]=cur[k] end
res[#res+1] = add
end
return
end
-- exclude
rec(i+1, cur)
-- include
cur[#cur+1] = arr[i]
rec(i+1, cur)
cur[#cur] = nil
end
rec(1, {})
return res
end

local function subset_labels(nonroot_odds)
-- sort the odds ascending for consistent labeling/order
local nums = {}
for i,x in ipairs(nonroot_odds) do nums[i]=x end
table.sort(nums)

local labels = {}
labels[#labels+1] = { text="Root", set={} }

local subsets = all_nonempty_subsets(nums)
-- order by size then lexicographic
table.sort(subsets, function(a,b)
if #a ~= #b then return #a < #b end
for i=1,math.min(#a,#b) do
if a[i] ~= b[i] then return a[i] < b[i] end
end
return #a < #b
end)
for _,set in ipairs(subsets) do
local parts={}
for i,od in ipairs(set) do parts[i] = "'" .. tostring(od) end
labels[#labels+1] = { text=table.concat(parts, ""), set=set }
end
return labels, nums -- also return the sorted nonroot odds
end

local function apply_octaves(enum, odds, chosen_set)
-- double entries whose odd is in chosen_set (set is table {odd=>true})
local out = {}
for i=1,#enum do
local v = enum[i]
if chosen_set[odds[i]] then v = v * 2 end
out[i] = v
end
return out
end

local function italicize(s) return "''" .. s .. "''" end
local function bold(s) return "'''" .. s .. "'''" end
local function bold_italic(s) return "'''''" .. s .. "'''''" end

-- -------- main render --------
function p.render(frame)
local args = frame.args or frame:getParent().args
local rchord_str = (args.rchord or args[1] or ""):gsub("%s+", "")
if rchord_str == "" then
return "<strong class=\"error\">Missing parameter: rchord</strong>"
end

local width = args.width or "120px"
local title = args.title or "Voicings and rotations around two octaves"
local cls = args.class or "wikitable sortable"

local enum = split_enum(rchord_str)
if #enum < 3 then
return "<strong class=\"error\">rchord must have at least 3 integers</strong>"
end

local rchord_display = rchord_str
local odds = toodds(enum)
local root_odd = odd_part(enum[1])
local odd_rows = unique_in_order(odds)

-- columns: Root + all subsets of non-root odds
local nonroot_odds_unique = {}
for _,o in ipairs(odd_rows) do
if o ~= root_odd then nonroot_odds_unique[#nonroot_odds_unique+1] = o end
end
local col_specs, nonroot_sorted = subset_labels(nonroot_odds_unique) -- {text,set}, and sorted list

local out = {}
out[#out+1] = "== " .. title .. " =="
out[#out+1] = string.format('{| class="%s" style="text-align:center;"', cls)
out[#out+1] = "|+"
out[#out+1] = string.format('! style="width:%s;" {{diagonal split header|Rotation|Voicing}}', width)
for _,spec in ipairs(col_specs) do
out[#out+1] = string.format('! style="width:%s;" | %s', width, spec.text)
end

-- rows
for _,rowodd in ipairs(odd_rows) do
out[#out+1] = "|-"
out[#out+1] = string.format('! style="width:%s;" | On %s', width, tostring(rowodd))

for _,spec in ipairs(col_specs) do
-- build chosen set for doubling
local chosen = {}
for _,od in ipairs(spec.set) do chosen[od] = true end

local base_voicing = apply_octaves(enum, odds, chosen)
local rotated = rotation_for_first_odd(base_voicing, rowodd, 8*#enum)

local disp = to_str(rotated)
local sortv = sort_key(rotated)
local shown
local is_two_octaves = (span_ratio(rotated) >= 4.0)

if rowodd == root_odd and #spec.set == 0 then
shown = bold_italic(disp)
elseif not is_two_octaves then
shown = italicize(disp)
else
shown = disp
end

out[#out+1] = string.format('| data-sort-value="%s" | %s', sortv, shown)
end
end

out[#out+1] = "|}"
out[#out+1] = "Enumerations in italics map to an existing octave-reduced rotation."
return table.concat(out, "\n")
end

return p

Module:ChordVoicings - Revision history

Eufalesio at 13:36, 11 November 2025

Eufalesio at 13:27, 11 November 2025

Eufalesio at 13:20, 11 November 2025

Eufalesio: Vibe coded v1.1

Eufalesio: Birth [Vibe coded v1]