Class: OPL::Helper

Inherits:
Object
  • Object
show all
Defined in:
lib/opl.rb

Class Method Summary collapse

Class Method Details

.add_ones(text, lp) ⇒ Object 



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# File 'lib/opl.rb', line 257

def self.add_ones(text, lp)
	equation = text
	equation = "#"+equation
	equation.scan(/[#+-][a-z]/).each do |p|
		if p.include?("+")
			q = p.gsub("+", "+1*")
		elsif p.include?("-")
			q = p.gsub("-","-1*")
		elsif p.include?("#")
			q = p.gsub("#","#1*")
		end
		equation = equation.gsub(p,q)
	end
	equation.gsub("#","")
end

.check_options_syntax(options) ⇒ Object 



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# File 'lib/opl.rb', line 717

def self.check_options_syntax(options)
	return if options.empty?
	options.each do |option|
		if option.include?(":")
			title = option.gsub(" ","").split(":")[0]
			value = option.gsub(" ","").split(":")[1]
			if !["nonnegative", "integer", "boolean", "data", "epsilon"].include?(title.downcase)
				raise "Did not recognize the TITLE parameter '#{title}' in the options."
			end
		else
			raise "Options parameter '#{option}' does not have a colon in it. The proper syntax of an option is TITLE: VALUE"
		end
	end
end

.coefficients(text, lp) ⇒ Object

text is one side of the equation



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# File 'lib/opl.rb', line 368

def self.coefficients(text, lp)#text is one side of the equation
	equation = self.add_ones(text, lp)
	if equation[0]=="-"
		equation.scan(/[+-][\d\.]+/)
	else
		("#"+equation).scan(/[#+-][\d\.]+/).map{|e|e.gsub("#","+")}
	end
end

.data_coefficients ⇒ Object 



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# File 'lib/opl.rb', line 377

def self.data_coefficients

end

.forall(text) ⇒ Object 



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# File 'lib/opl.rb', line 170

def self.forall(text)
	#in: "i in (0..2), x[i] <= 5"
	#out: ["x[0] <= 5", "x[1] <= 5", "x[2] <= 5"]
	helper = self
	text = text.sub_paren_with_array
	if ((text.gsub(" ","")).scan(/\]\,/).size) + ((text.gsub(" ","")).scan(/\)\,/).size) != text.gsub(" ","").scan(/in/).size
		raise "The following forall() constraint is incorrectly formatted: #{text}. Please see the examples in test.rb for forall() constraints. I suspect you are missing a comma somewhere."
	end
	final_constraints = []
	if text.include?("sum")
		indices = text.split("sum")[0].scan(/[a-z] in/).map{|sc|sc[0]}
		values = text.split("sum")[0].scan(/\s\[[\-\s\d+,]+\]/).map{|e|e.gsub(" ", "").scan(/[\-\d]+/)}
	else
		indices = text.scan(/[a-z] in/).map{|sc|sc[0]}
		values = text.scan(/\s\[[\-\s\d+,]+\]/).map{|e|e.gsub(" ", "").scan(/[\-\d]+/)}
	end
	#TODO: the indices and values should only be those
		#of the forall(), not of any sum() that is
		#inside the forall()
	index_value_pairs = indices.zip(values)
	variable = text.scan(/[a-z]\[/)[0].gsub("[","")
	value_combinations = helper.mass_product(values)
	value_combinations.each_index do |vc_index|
		value_combination = value_combinations[vc_index]
		value_combination = [value_combination] unless value_combination.is_a?(Array)
		if text.include?("sum")
			constraint = "sum"+text.split("sum")[1..-1].join("sum")
		else
			constraint = text.split(",")[-1].gsub(" ","")
		end
		e = constraint
		value_combination.each_index do |i|
			index = indices[i]
			value = value_combination[i]
			e = e.gsub("("+index, "("+value)
			e = e.gsub(index+")", value+")")
			e = e.gsub("["+index, "["+value)
			e = e.gsub(index+"]", value+"]")
			e = e.gsub("=>"+index, "=>"+value)
			e = e.gsub("<="+index, "<="+value)
			e = e.gsub(">"+index, ">"+value)
			e = e.gsub("<"+index, "<"+value)
			e = e.gsub("="+index, "="+value)
			e = e.gsub("=> "+index, "=> "+value)
			e = e.gsub("<= "+index, "<= "+value)
			e = e.gsub("> "+index, "> "+value)
			e = e.gsub("< "+index, "< "+value)
			e = e.gsub("= "+index, "= "+value)
		end
		final_constraints += [e]
	end
	final_constraints
end

.get_all_vars(constraints, lp) ⇒ Object 



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# File 'lib/opl.rb', line 386

def self.get_all_vars(constraints, lp)
	all_vars = []
	constraints.each do |constraint|
		constraint = constraint.gsub(" ", "")
		value = constraint.split(":")[1] || constraint
		all_vars << self.variables(value, lp)
	end
	all_vars.flatten.uniq
end

.get_coefficient_variable_pairs(text) ⇒ Object 



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# File 'lib/opl.rb', line 474

def self.get_coefficient_variable_pairs(text)
	text.scan(/\d*[\*]*[a-z]\[*\d*\]*/)
end

.get_column_bounds(bound_info, all_variables) ⇒ Object 



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# File 'lib/opl.rb', line 608

def self.get_column_bounds(bound_info, all_variables)
	#in: ["NONNEGATIVE: x1"]
	#out: {:x1 => {:lower => 0}}
	column_bounds = {}
	bound_info.each do |info|
		type = info.gsub(" ","").split(":")[0]
		if type.downcase == "nonnegative"
			bounds = {:lower => 0}
		end
		variables = info.split(":")[1].gsub(" ","").split(",")
		variables.each do |root_var|
			all_variables_with_root = all_variables.find_all{|var|var.include?("[") && var.split("[")[0]==root_var}+[root_var]
			all_variables_with_root.each do |var|
				column_bounds[var.to_sym] = bounds
			end
		end
	end
	column_bounds
end

.get_constants(text) ⇒ Object 



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# File 'lib/opl.rb', line 396

def self.get_constants(text)
	#in: "-8 + x + y + 3"
	#out: "[-8, +3]"
	text = text.gsub(" ","")
	text = text+"#"
	cs = []
	potential_constants = text.scan(/[\d\.]+[^a-z^\[^\]^\d^\.^\)^\*]/)
	constants = potential_constants.find_all{|c|![*('a'..'z'),*('A'..'Z'),"["].include?(text[text.index(c)-1])}
	searchable_text = text
	constants.each_index do |i|
		constant = constants[i]
		c = constant.scan(/[\d\.]+/)[0]
		index = searchable_text.index(constant)
		if index == 0
			c = "+"+c
		else
			constant = constant.gsub('+','[+]')
			constant = constant.gsub('-','[-]')
			c = searchable_text.scan(/[\-\+]#{constant}/)[0]
		end
		cs << c.scan(/[\-\+][\d\.]+/)[0]
		searchable_text[index] = "**"
	end
	return({:formatted => cs, :unformatted => constants})
end

.mass_product(array_of_arrays, base = []) ⇒ Object 



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# File 'lib/opl.rb', line 159

def self.mass_product(array_of_arrays, base=[])
	return(base) if array_of_arrays.empty?
	array = array_of_arrays[0]
	new_array_of_arrays = array_of_arrays[1..-1]
	if base==[]
		self.mass_product(new_array_of_arrays, array)
	else
		self.mass_product(new_array_of_arrays, base.product(array).map{|e|e.flatten})
	end
end

.operator(constraint) ⇒ Object 



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# File 'lib/opl.rb', line 478

def self.operator(constraint)
	if constraint.include?(">=")
		">="
	elsif constraint.include?("<=")
		"<="
	elsif constraint.include?(">")
		">"
	elsif constraint.include?("<")
		"<"
	elsif constraint.include?("=")
		"="
	end
end

.parse_data(data_info) ⇒ Object 



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# File 'lib/opl.rb', line 628

def self.parse_data(data_info)
	#in: "DATA: {d => [1, 0.3, 1.5], o => [10.3, 4.0005, -1]}"
	#out: [data_object_1, data_object_2]
	data_hash_string = data_info.gsub(" ","").split(":")[1]
	data_string = data_hash_string.gsub("{",",").gsub("}",",")
	names = data_string.scan(/,[a-z]/).map{|comma_name|comma_name.gsub(",","")}
	string_values = data_string.scan(/\=\>[\[\d\.\]\,\-]+,/).map{|scanned_value|scanned_value[2..-2]}
	values = string_values.map{|sv|sv.to_a}
	data_hash = {}
	names.each_index do |i|
		name = names[i]
		value = values[i]
		value = value[0] if value.size == 1
		data_hash[name] = value
	end
	return(data_hash)
end

.produce_variable_type_hash(variable_types, all_variables) ⇒ Object 



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# File 'lib/opl.rb', line 555

def self.produce_variable_type_hash(variable_types, all_variables)
	#in: ["BOOLEAN: x, y", "INTEGER: z"]
	#out: {:x => 3, :y => 3, :z => 2}
	variable_type_hash = {}
	variable_types.each do |vt|
		type = vt.gsub(" ","").split(":")[0]
		if type.downcase == "boolean"
			type_number = 3
		elsif type.downcase == "integer"
			type_number = 2
		end
		variables = vt.split(":")[1].gsub(" ","").split(",")
		variables.each do |root_var|
			all_variables_with_root = all_variables.find_all{|var|var.include?("[") && var.split("[")[0]==root_var}+[root_var]
			all_variables_with_root.each do |var|
				variable_type_hash[var.to_sym] = type_number
			end
		end
	end
	variable_type_hash
end

.put_constants_on_rhs(text) ⇒ Object 



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# File 'lib/opl.rb', line 422

def self.put_constants_on_rhs(text)
	#in: "-8 + x + y + 3 <= 100"
	#out: "x + y <= 100 + 5"
	text = text.gsub(" ","")
	s = self.sides(text)
	constants_results = self.get_constants(s[:lhs])
	constants = []
	constants_results[:formatted].each_index do |i|
		formatted_constant = constants_results[:formatted][i]
		unformatted_constant = constants_results[:unformatted][i]
		unless unformatted_constant.include?("*")
			constants << formatted_constant
		end
	end
	unless constants.empty?
		sum = constants.map{|cc|cc.to_f}.inject("+").to_s
		if sum.include?("-")
			sum = sum.gsub("-","+")
		else
			sum = "-"+sum
		end
		lhs = s[:lhs].gsub(" ","")+"#"
		constants_results[:unformatted].each do |constant|
			index = lhs.index(constant)
			if index == 0
				lhs = lhs[(constant.size-1)..(lhs.size-1)]
			else
				lhs = lhs[0..(index-2)]+lhs[(index+(constant.size-1))..(lhs.size-1)]
			end
		end
		text = text.gsub(s[:lhs], lhs[0..-2])
		text += sum
	end
	return(text)
end

.put_variables_on_lhs(text) ⇒ Object 



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# File 'lib/opl.rb', line 492

def self.put_variables_on_lhs(text)
	#in: "x + y - x[3] <= 3z + 2x[2] - 10"
	#out: "x + y - x[3] - 3z - 2x[2] <= -10"
	text = text.gsub(" ", "")
	s = self.sides(text)
	oper = self.operator(text)
	rhs = s[:rhs]
	lhs = s[:lhs]
	coefficient_variable_pairs = self.get_coefficient_variable_pairs(rhs)
	add_to_left = []
	remove_from_right = []
	coefficient_variable_pairs.each do |cvp|
		index = rhs.index(cvp)
		if index == 0
			add_to_left << "-"+cvp
			remove_from_right << cvp
		else
			if rhs[index-1] == "+"
				add_to_left << "-"+cvp
				remove_from_right << "+"+cvp
			else
				add_to_left << "+"+cvp
				remove_from_right << "-"+cvp
			end
		end
	end
	new_lhs = lhs+add_to_left.join("")
	text = text.gsub(lhs+oper, new_lhs+oper)
	new_rhs = rhs
	remove_from_right.each do |rfr|
		new_rhs = new_rhs.gsub(rfr, "")
	end
	new_rhs = "0" if new_rhs == ""
	text = text.gsub(oper+rhs, oper+new_rhs)
	return(text)
end

.remove_constants(text) ⇒ Object 



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# File 'lib/opl.rb', line 682

def self.remove_constants(text)
	helper = self
	text = text.gsub(" ","")
	text = "+"+text if text[0]!="-"
	text = text+"#"
	constants = helper.get_constants(text)
	replacements = []
	constants[:formatted].each_index do |i|
		formatted = constants[:formatted][i]
		unformatted = constants[:unformatted][i]
		if formatted.include?("+")
			if unformatted.include?("+")
				replacements << ["+"+unformatted, "+"]
			elsif unformatted.include?("-")
				replacements << ["-"+unformatted, "-"]
			elsif unformatted.include?("#")
				replacements << [formatted+"#",""]
			end
		elsif formatted.include?("-")
			if unformatted.include?("+")
				replacements << ["-"+unformatted, "+"]
			elsif unformatted.include?("-")
				replacements << ["-"+unformatted, "-"]
			elsif unformatted.include?("#")
				replacements << [formatted+"#",""]
			end
		end
	end
	replacements.each do |replacement|
		text = text.gsub(replacement[0],replacement[1])
	end
	text = text[1..-1] if text[0] == "+"
	return(text)
end

.sides(text) ⇒ Object 



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# File 'lib/opl.rb', line 240

def self.sides(text)
	equation = text
	if equation.include?("<=")
		char = "<="
	elsif equation.include?(">=")
		char = ">="
	elsif equation.include?("<")
		char = "<"
	elsif equation.include?(">")
		char = ">"
	elsif equation.include?("=")
		char = "="
	end
	sides = equation.split(char)
	{:lhs => sides[0], :rhs => sides[1]}
end

.split_equals(constraint) ⇒ Object 



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# File 'lib/opl.rb', line 529

def self.split_equals(constraint)
	[constraint.gsub("=", "<="), constraint.gsub("=", ">=")]
end

.split_equals_a(constraints) ⇒ Object 



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# File 'lib/opl.rb', line 533

def self.split_equals_a(constraints)
	constraints.map do |constraint|
		if (constraint.split("") & ["<=",">=","<",">"]).empty?
			self.split_equals(constraint)
		else
			constraint
		end
	end.flatten
end

.sub_forall(equation, indexvalues = {:indices => [], :values => []}) ⇒ Object 



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# File 'lib/opl.rb', line 224

def self.sub_forall(equation, indexvalues={:indices => [], :values => []})
	#in: "forall(i in (0..2), x[i] <= 5)"
	#out: ["x[0] <= 5", "x[1] <= 5", "x[2] <= 5"]
	return equation unless equation.include?("forall")
	foralls = (equation+"#").split("forall(").map{|ee|ee.split(")")[0..-2].join(")")}.find_all{|eee|eee!=""}
	constraints = []
	if foralls.empty?
		return(equation)
	else
		foralls.each do |text|
			constraints << self.forall(text)
		end
		return(constraints.flatten)
	end
end

.sub_rhs_with_summed_constants(constraint) ⇒ Object 



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# File 'lib/opl.rb', line 469

def self.sub_rhs_with_summed_constants(constraint)
	rhs = self.sides(constraint)[:rhs]
	constraint.gsub(rhs, self.sum_constants(rhs))
end

.sub_sum(equation, lp, indexvalues = {:indices => [], :values => []}) ⇒ Object 



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# File 'lib/opl.rb', line 335

def self.sub_sum(equation, lp, indexvalues={:indices => [], :values => []})
	#in: "sum(i in (0..3), x[i]) <= 100"
	#out: "x[0]+x[1]+x[2]+x[3] <= 100"
	sums = (equation+"#").split("sum(").map{|ee|ee.split(")")[0..-2].join(")")}.find_all{|eee|eee!=""}.find_all{|eeee|!eeee.include?("forall")}
	sums.each do |text|
		e = text
		unless indexvalues[:indices].empty?
			indexvalues[:indices].each_index do |i|
				index = indexvalues[:indices][i]
				value = indexvalues[:values][i].to_s
				e = e.gsub("("+index, "("+value)
				e = e.gsub(index+")", value+")")
				e = e.gsub("["+index, "["+value)
				e = e.gsub(index+"]", value+"]")
				e = e.gsub("=>"+index, "=>"+value)
				e = e.gsub("<="+index, "<="+value)
				e = e.gsub(">"+index, ">"+value)
				e = e.gsub("<"+index, "<"+value)
				e = e.gsub("="+index, "="+value)
				e = e.gsub("=> "+index, "=> "+value)
				e = e.gsub("<= "+index, "<= "+value)
				e = e.gsub("> "+index, "> "+value)
				e = e.gsub("< "+index, "< "+value)
				e = e.gsub("= "+index, "= "+value)
			end
		end
		equation = equation.gsub(text, e)
		result = self.sum(text, lp)
		equation = equation.gsub("sum("+text+")", result)
	end
	return(equation)
end

.substitute_data(text, lp) ⇒ Object 



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# File 'lib/opl.rb', line 646

def self.substitute_data(text, lp)
	helper = self
	potential_things_to_substitute = helper.variables(text, lp)
	data_names = lp.data.map{|d|d.name}
	things_to_substitute = {}
	data_values = {}
	lp.data.each do |data|
		dname = data.name
		dvalue = data.value
		targets = potential_things_to_substitute.find_all do |ptts|
			dname == ptts[0]
		end
		things_to_substitute[dname] = targets
		targets.each do |target|
			indices = target.scan(/\d+/).map{|ind|ind.to_i}
			indices = "" if indices.empty?
			if dvalue.is_a?(Array)
				value = dvalue.values_at_a(indices)
			else
				value = dvalue
			end
			data_values[dname+indices.to_s.gsub(",","][").gsub(" ","")] = value
		end
	end
	data_values.keys.each do |key|
		name = key
		value = data_values[key]
		text = text.gsub(name, value.to_s)
	end
	plus_minus = text.scan(/\+[\ ]+-/)
	plus_minus.each do |pm|
		text = text.gsub(pm,"-")
	end
	return(text)
end

.sum(text, lp, indexvalues = {:indices => [], :values => []}) ⇒ Object 



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# File 'lib/opl.rb', line 273

def self.sum(text, lp, indexvalues={:indices => [], :values => []})
	#in: "i in [0,1], j in [4,-5], 3x[i][j]"
	#out: "3x[0][4] + 3x[0][-5] + 3x[1][4] + 3x[1][-5]"
	text = text.sub_paren_with_array
	if (text.gsub(" ","")).scan(/\]\,/).size != text.scan(/in/).size
		raise "The following sum() constraint is incorrectly formatted: #{text}. Please see the examples in test.rb for sum() constraints. I suspect you are missing a comma somewhere."
	elsif (text.gsub(" ","").include?("=") || text.gsub(" ","").include?("<") || text.gsub(" ","").include?(">"))
		raise "The following sum() constraint cannot have a equalities in it (a.k.a. =, <, >): #{text}"
	end
	final_text = ""
	element = text.split(",")[-1].gsub(" ","")
	indices = text.scan(/[a-z] in/).map{|sc|sc[0]}
	input_indices = indexvalues[:indices] - indices
	if not input_indices.empty?
		input_values = input_indices.map{|ii|indexvalues[:values][indexvalues[:indices].index(ii)]}
	else
		input_values = []
	end
	values = text.scan(/\s\[[\-\s\d+,]+\]/).map{|e|e.gsub(" ", "").scan(/[\-\d]+/)}
	indices += input_indices
	values += input_values
	index_value_pairs = indices.zip(values)
	variable = text.scan(/[a-z]\[/)[0].gsub("[","")
	coefficient_a = text.split(",")[-1].split("[")[0].scan(/\-?[\d\*]+[a-z]/)
	if coefficient_a.empty?
		if text.split(",")[-1].split("[")[0].include?("-")
			coefficient = "-1"
		else
			coefficient = "1"
		end
	else
		coefficient = coefficient_a[0].scan(/[\d\-]+/)
	end
	value_combinations = OPL::Helper.mass_product(values)
	value_combinations.each_index do |vc_index|
		value_combination = value_combinations[vc_index]
		e = element
		value_combination = [value_combination] unless value_combination.is_a?(Array)
		value_combination.each_index do |i|
			index = indices[i]
			value = value_combination[i]
			e = e.gsub("("+index, "("+value)
			e = e.gsub(index+")", value+")")
			e = e.gsub("["+index, "["+value)
			e = e.gsub(index+"]", value+"]")
			e = e.gsub("=>"+index, "=>"+value)
			e = e.gsub("<="+index, "<="+value)
			e = e.gsub(">"+index, ">"+value)
			e = e.gsub("<"+index, "<"+value)
			e = e.gsub("="+index, "="+value)
			e = e.gsub("=> "+index, "=> "+value)
			e = e.gsub("<= "+index, "<= "+value)
			e = e.gsub("> "+index, "> "+value)
			e = e.gsub("< "+index, "< "+value)
			e = e.gsub("= "+index, "= "+value)
		end
		e = "+"+e unless (coefficient.include?("-") || vc_index==0)
		final_text += e
	end
	final_text
end

.sum_constants(text) ⇒ Object 



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# File 'lib/opl.rb', line 458

def self.sum_constants(text)
	#in: "100+ 10-3"
	#out: "107"
	constants = self.get_constants(text)[:formatted]
	if constants.to_s.include?(".")
		constants.map{|c|c.to_f}.inject("+").to_s
	else
		constants.map{|c|c.to_i}.inject("+").to_s
	end
end

.sum_indices(constraint) ⇒ Object 



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# File 'lib/opl.rb', line 543

def self.sum_indices(constraint)
	#pieces_to_sub = constraint.scan(/[a-z]\[\d[\d\+\-]+\]/)
	pieces_to_sub = constraint.scan(/[a-z\]]\[\d[\d\+\-]+\]/)
	pieces_to_sub.each do |piece|
		characters_to_sum = piece.scan(/[\d\+\-]+/)[0]
		index_sum = self.sum_constants(characters_to_sum)
		new_piece = piece.gsub(characters_to_sum, index_sum)
		constraint = constraint.gsub(piece, new_piece)
	end
	return(constraint)
end

.sum_variables(formatted_constraint, lp) ⇒ Object 



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# File 'lib/opl.rb', line 577

def self.sum_variables(formatted_constraint, lp)
	#in: x + y - z + x[3] + z + y - z + x - y <= 0
	#out: 2*x + y - z + x[3] <= 0
	helper = self
	lhs = helper.sides(formatted_constraint)[:lhs]
	formatted_lhs = helper.add_ones(lhs, lp)
	vars = helper.variables(formatted_lhs, lp)
	coefs = helper.coefficients(formatted_lhs, lp)
	var_coef_hash = {}
	vars.each_index do |i|
		var = vars[i]
		coef = coefs[i]
		if var_coef_hash[var]
			var_coef_hash[var] += coefs[i].to_f
		else
			var_coef_hash[var] = coefs[i].to_f
		end
	end
	new_lhs = ""
	var_coef_hash.keys.each do |key|
		coef = var_coef_hash[key].to_s
		var = key
		coef = "+"+coef unless coef.include?("-")
		new_lhs += coef+"*"+var
	end
	if new_lhs[0] == "+"
		new_lhs = new_lhs[1..-1]
	end
	formatted_constraint.gsub(lhs, new_lhs)
end

.variables(text, lp) ⇒ Object

parameter is one side of the equation



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# File 'lib/opl.rb', line 381

def self.variables(text, lp)#parameter is one side of the equation
	equation = self.add_ones(text, lp)
	equation.scan(/[a-z]+[\[\]\d]*/)
end