Module:MOS degrees: Difference between revisions

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@@ Line 156: / Line 156: @@
 	return rows
+end
+-- Helper function; FOR FUTURE REWRITE
+-- Creates the column for the note name
+-- Decoupled degree and note name functions allow note names being omitted.
+function p.preprocess_note_names(input_mos, udp, note_symbols, sharp_symbol, flat_symbol, asc_chain_length, des_chain_length)
+	-- Test parameters
+	--[[
+	local input_mos = input_mos or mos.new(5, 2, 2)
+	local udp = udp or { 5, 1 }
+	local note_symbols = note_symbols or "CDEFGAB"
+	local sharp_symbol = sharp_symbol or "#"
+	local flat_symbol = flat_symbol or "b"
+	local asc_chain_length = input_mos.nL * 2 + input_mos.ns
+	local des_chain_length = input_mos.nL * 2 + input_mos.ns
+	]]--
+	-- Get the number of mossteps per period and equave
+	local mossteps_per_equave = input_mos.nL + input_mos.ns
+	local periods_per_equave = rat.gcd(input_mos.nL, input_mos.ns)
+	local mossteps_per_period = mossteps_per_equave / periods_per_equave
+	-- How long are the initial genchain lengths? (These correspond to the UDP)
+	local gens_up_per_period = udp[1] / periods_per_equave
+	local gens_dn_per_period = udp[2] / periods_per_equave
+	-- Get the genchains
+	local asc_genchain = mosnot.mos_nomacc_chain(input_mos, gens_up_per_period, asc_chain_length, true)
+	local des_genchain = mosnot.mos_nomacc_chain(input_mos, gens_dn_per_period, des_chain_length, false)
+	-- Calculate the entries for each cell
+	local column = {}
+	for i = 1, periods_per_equave do
+		-- Add degrees from ascending chain
+		for j = 1, asc_chain_length do
+			local mossteps = asc_genchain[i][j]['mossteps']
+			local chromas  = asc_genchain[i][j]['chromas']
+			-- Find the note name
+			local note_symbol = string.sub(note_symbols, mossteps + 1, mossteps + 1)
+			local note_name = mosnot.mosstep_and_chroma_to_note_name(mossteps, chromas, note_symbol, sharp_symbol)
+			table.insert(column, note_name)
+		end
+		-- Calculate the stop value for the for loop as being 1 or 2, depending
+		-- on whether this is the last period or not
+		local stop_value = 1
+		if i ~= periods_per_equave then
+			stop_value = stop_value + 1
+		end
+		-- Add degrees from descending chain
+		-- The descending chain differs from the ascending chain:
+		-- - The descending chain should follow after the ascending chain.
+		-- - The descending chain's entries should be added backwards and skip
+		--   the root.
+		-- - This way, if the mos is multi-period, the root of the next period's
+		--   ascending chain (which is the same as the current period's descend-
+		--   ing chain) won't be added twice.
+		-- - If the period is the last period, add the root as the equave.
+		for j = des_chain_length, stop_value, -1 do
+			local mossteps = des_genchain[i][j]['mossteps']
+			local chromas  = des_genchain[i][j]['chromas']
+			-- Find the note name
+			-- If the mosstep is the root of the period, add a period to it
+			local note_symbol = string.sub(note_symbols, mossteps + 1, mossteps + 1)
+			if mossteps % mossteps_per_period == 0 then
+				mossteps = mossteps + mossteps_per_period
+			end
+			local note_name = mosnot.mosstep_and_chroma_to_note_name(mossteps, chromas, note_symbol, flat_symbol)
+			table.insert(column, note_name)
+		end
+	end
+	return column
 end
 -- Helper function; FOR FUTURE REWRITE
 -- Creates the column for the degree name
--- Decoupled degree names function to allow note names being omitted.
+-- Decoupled degree and note name functions allow note names being omitted.
 function p.preprocess_degrees(input_mos, asc_chain_length, des_chain_length, prefix, notation)
 	-- Test parameters
@@ Line 193: / Line 271: @@
 			end
-			local cell = degree_name
+			table.insert(column, degree_name)
-			table.insert(column, cell)
 		end
@@ Line 232: / Line 309: @@
 			end
-			local cell = degree_name
+			table.insert(column, degree_name)
-			table.insert(column, cell)
 		end
 	end