Module:Harmonic entropy: Difference between revisions

Plumtree (talk | contribs)
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Plumtree (talk | contribs)
Deprecating ET parsing and backslash ratio: those were ET-specific and not interval-specific. Functionality moved into Module:ET
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return u._round(result, prec)
return u._round(result, prec)
end
end
end
-- edf = ed3/2, edo = ed2, edt = ed3
local equaves =
{
  ['f'] = rat.new(3, 2),
  ['o'] = 2,
  ['t'] = 3
}
-- returns size of an ET given its name
function p.parse_ET_size(frame)
local args = getArgs(frame)
local size, equave = p.parse_ET(args[1])
return size
end
-- returns equave of an ET given its name
function p.parse_ET_equave(frame)
local args = getArgs(frame)
local size, equave = p.parse_ET(args[1])
return rat.as_float(equave)
end
-- returns size and equave of an ET given its name; cannot be used with {{#invoke:}}
function p.parse_ET(input)
input = string.lower(input)
local size, equave
-- size defaults to 12
size = u.eval_num_arg(input:match("^([0-9]+)"), 12)
if input:match("^[0-9]*[%-]?ed[fot]$") then
equave = equaves[tostring(input:match("[fot]"))]
else
-- equave defaults to 2
equave = rat.parse(input:match("^.-ed(.+)%s*$")) or 2
end
return size, equave
end
-- return ratio corresponding to an interval written in backslash notation
-- ("steps" of "size" equal divisions of the "equave")
function p.backslash_ratio(frame)
local args = getArgs(frame)
return p._backslash_ratio(args[1])
end
function p._backslash_ratio(input)
-- result defaults to 0
local result = 0
-- steps defaults to 1
local steps = input:match("%s*(%-?[0-9]+)\\.-") or 1
local size, equave = p.parse_ET(input:match("\\(.*)"))
if tonumber(size) == 0 then
return 1
end
result = rat.as_float(equave)^(tonumber(steps)/tonumber(size))
return result
end
end


return p
return p