Module:Mediants: Difference between revisions

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@@ Line 1: / Line 1: @@
+local rat   = require("Module:Rational")
 local utils = require("Module:Utils")
 local p = {}
--- TODO:
--- - Add a convert-to-rational function.
--- - Add sort function
 --------------------------------------------------------------------------------
@@ Line 22: / Line 19: @@
 end
--- Given a ratio, return its simplified form
+-- Given a ratio, return its simplified form.
 function p.simplify_ratio(ratio)
 	local gcd = utils._gcd(ratio[1], ratio[2])
@@ Line 28: / Line 25: @@
 end
--- Sort ratios in ascending order (TODO)
+-- Sort ratios in ascending order. Comparison function is built-in.
+function p.sort_ratios(ratios)
+	table.sort(ratios, function(ratio_1, ratio_2)
+		return ratio_1[1] / ratio_1[2] < ratio_2[1] / ratio_2[2]
+		end
+	)
+end
--- Comparison function for use with Lua's sort function (TODO)
+-- Given a single ratio, as a table of two numbers, convert to rational and
+-- return it.
+function p.to_rational(ratio)
+	return rat.new(ratio[1], ratio[2])
+end
+-- Given a table of ratios, each a table of two numbers, return an array of
+-- ratios in the form as defined by module:Rational.
+function p.to_rationals(ratios)
+	local rats = {}
+	for i = 1, #ratios do
+		table.insert(rats, p.to_rational(ratios[i]))
+	end
+	return rats
+end
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@@ Line 196: / Line 213: @@
 function p.tester()
-	return p.find_only_mediants_by_int_limit()
+	--return p.find_only_mediants_by_int_limit()
+	local ratios = {{4,3}, {5,1}, {3,2}}
+	p.sort_ratios(ratios)
+	return p.to_rationals(ratios)
 end
 return p