Class: Gecode::FreeIntVar

Inherits:
Object
  • Object
show all
Includes:
Constraints::LeftHandSideMethods
Defined in:
lib/gecoder/interface/variables.rb,
lib/gecoder/interface/constraints/int/linear.rb,
lib/gecoder/interface/constraints/int/arithmetic.rb,
lib/gecoder/interface/constraints/int_var_constraints.rb

Overview

Describes an integer variable. Each integer variable has a domain of several integers which represent the possible values that the variable may take. An integer variable is said to be assigned once the domain only contains a single element, at which point #value can be used to retrieve the value.

Instance Method Summary collapse

Methods included from Constraints::LeftHandSideMethods

#must, #must_not

Instance Method Details

#*(var) ⇒ Object

Begins a multiplication constraint involving the two int variable.



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# File 'lib/gecoder/interface/constraints/int/linear.rb', line 13

def *(int)
  if int.kind_of? Fixnum
    Gecode::Constraints::Int::Linear::ExpressionNode.new(self, 
      @model) * int
  else
    pre_linear_mult(int) if respond_to? :pre_linear_mult
  end
end

#+(var) ⇒ Object

Creates a linear expression where the int variables are summed.



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# File 'lib/gecoder/interface/constraints/int/linear.rb', line 4

def +(var)
  Gecode::Constraints::Int::Linear::ExpressionNode.new(self, 
    @model) + var
end

#-(var) ⇒ Object

Creates a linear expression where the specified variable is subtracted from this one.



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# File 'lib/gecoder/interface/constraints/int/linear.rb', line 24

def -(var)
  Gecode::Constraints::Int::Linear::ExpressionNode.new(self, 
    @model) - var
end

#abs ⇒ Object

Initiates an arithmetic absolute value constraint.



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# File 'lib/gecoder/interface/constraints/int/arithmetic.rb', line 3

def abs
  Gecode::Constraints::Int::Arithmetic::AbsExpressionStub.new(@model, 
    :lhs => self)
end

#pre_arith_mult ⇒ Object

Creates a linear expression where the int variable is multiplied with a constant integer.



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# File 'lib/gecoder/interface/constraints/int/arithmetic.rb', line 22

def *(int)
  if int.kind_of? Fixnum
    Gecode::Constraints::Int::Linear::ExpressionNode.new(self, 
      @model) * int
  else
    pre_linear_mult(int) if respond_to? :pre_linear_mult
  end
end

#pre_linear_mult ⇒ Object 



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# File 'lib/gecoder/interface/constraints/int/linear.rb', line 9

alias_method :pre_linear_mult, :*

#sqrt ⇒ Object Also known as: square_root

Initiates an arithmetic squared root constraint.



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# File 'lib/gecoder/interface/constraints/int/arithmetic.rb', line 15

def sqrt
  Gecode::Constraints::Int::Arithmetic::SquareRootExpressionStub.new(@model, 
    :lhs => self)
end

#squared ⇒ Object

Initiates an arithmetic squared value constraint.



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# File 'lib/gecoder/interface/constraints/int/arithmetic.rb', line 9

def squared
  Gecode::Constraints::Int::Arithmetic::SquaredExpressionStub.new(@model, 
    :lhs => self)
end

#value ⇒ Object

Gets the value of the assigned integer variable (a Fixnum). The variable must be assigned, if it isn’t then a RuntimeError is raised.



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# File 'lib/gecoder/interface/variables.rb', line 96

def value
  raise 'No value is assigned.' unless assigned?
  send_bound(:val)
end