Class: Gecode::Bool::Linear::ExpressionTree

Inherits:
Int::ShortCircuitRelationsOperand show all
Includes:
BoolLinearOperations
Defined in:
lib/gecoder/interface/constraints/bool/linear.rb

Overview

Describes a binary tree of expression nodes which together form a linear expression.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from BoolLinearOperations

#*, #+, #-

Methods inherited from Int::ShortCircuitRelationsOperand

#to_int_var

Methods included from Int::IntOperand

#*, #+, #-, #abs, #method_missing, #pre_arith_mult, #square_root, #squared

Methods included from Operand

#must, #must_not

Constructor Details

#initialize(left_node, right_node, operation) ⇒ ExpressionTree

Constructs a new expression with the specified operands.



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# File 'lib/gecoder/interface/constraints/bool/linear.rb', line 125

def initialize(left_node, right_node, operation)
  super(left_node.model || right_node.model)
  @left = left_node
  @right = right_node
  @operation = operation
  @model = @left.model || @right.model
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class Gecode::Int::IntOperand

Instance Attribute Details

#model ⇒ Object (readonly)

Returns the value of attribute model.



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# File 'lib/gecoder/interface/constraints/bool/linear.rb', line 122

def model
  @model
end

Instance Method Details

#construct_receiver(params) ⇒ Object 



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# File 'lib/gecoder/interface/constraints/bool/linear.rb', line 140

def construct_receiver(params)
  receiver = pre_bool_construct_receiver(params)
  lhs = self
  receiver.instance_eval{ @lhs = lhs }
  class <<receiver
    alias_method :pre_bool_equality, :==
    def ==(op, options = {})
      if op.respond_to? :to_bool_var
        (@lhs - op).must.equal(0, options)
      else
        pre_bool_equality(op, options)
      end
    end
    alias_comparison_methods
  end
  return receiver
end

#pre_bool_construct_receiver ⇒ Object 



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# File 'lib/gecoder/interface/constraints/bool/linear.rb', line 139

alias_method :pre_bool_construct_receiver, :construct_receiver

#relation_constraint(relation, bool_operand_or_fix, params) ⇒ Object 



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# File 'lib/gecoder/interface/constraints/bool/linear.rb', line 158

def relation_constraint(relation, bool_operand_or_fix, params)
  unless params[:negate]
    relation_type = 
      Gecode::Util::RELATION_TYPES[relation]
  else
    relation_type = 
      Gecode::Util::NEGATED_RELATION_TYPES[relation]
  end

  unless bool_operand_or_fix.respond_to? :to_minimodel_lin_exp
    bool_operand_or_fix = Linear::ExpressionNode.new(bool_operand_or_fix);
  end

  params.update(:rhs => bool_operand_or_fix, :relation_type => relation_type)
  LinearRelationConstraint.new(model, params)
end

#to_minimodel_lin_exp ⇒ Object

Converts the linear expression to an instance of Gecode::Raw::MiniModel::LinExpr



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# File 'lib/gecoder/interface/constraints/bool/linear.rb', line 135

def to_minimodel_lin_exp
  @left.to_minimodel_lin_exp.send(@operation, @right.to_minimodel_lin_exp)
end