Class: RedShift::FlowSyntax::FlowParser

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(block) ⇒ FlowParser

Returns a new instance of FlowParser.



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# File 'lib/redshift/syntax.rb', line 212

def initialize block
  @flows = []
  val = instance_eval(&block)
  if val.kind_of? String and val =~ /=/
    warn "Equation appears to be missing a specifier (alg, diff, etc.):" +
      val
  end
end

Instance Attribute Details

#flows ⇒ Object (readonly)

Returns the value of attribute flows.



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# File 'lib/redshift/syntax.rb', line 210

def flows
  @flows
end

Instance Method Details

#algebraic(*equations) ⇒ Object Also known as: alg 



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# File 'lib/redshift/syntax.rb', line 221

def algebraic(*equations)
  equations.each do |equation|
    unless equation =~ /^\s*(\w+)\s*=\s*(.+)/m
      raise SyntaxError, "parse error in\n\t#{equation}."
    end
    @flows << AlgebraicFlow.new($1.intern, $2.strip)
  end
end

#delay(*equations) ⇒ Object 



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# File 'lib/redshift/syntax.rb', line 267

def delay(*equations)
  opts = equations.pop
  unless opts and opts.kind_of? Hash and opts[:by]
    raise SyntaxError, "Missing delay term: :delay => <delay>"
  end
  delay_by = opts[:by]
  equations.each do |equation|
    unless equation =~ /^\s*(\w+)\s*=\s*(.+)/m
      raise SyntaxError, "parse error in\n\t#{equation}."
    end
    @flows << DelayFlow.new($1.intern, $2.strip, delay_by)
  end
end

#derive(*equations) ⇒ Object 



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# File 'lib/redshift/syntax.rb', line 248

def derive(*equations)
  opts = equations.pop
  unless opts and opts.kind_of? Hash and
         (opts[:feedback] == true or opts[:feedback] == false)
    raise SyntaxError, "Missing option: :feedback => <true|false>\n" +
      "Use 'true' when the output of this flow feeds back into another\n" +
      "derivative flow (even after a delay). Also, set <var>_init_rhs.\n"
    ## should false be the default?
    ## rename 'feedback'?
  end
  feedback = opts[:feedback]
  equations.each do |equation|
    unless equation =~ /^\s*(\w+)\s*=\s*(.+)'\s*\z/m
      raise SyntaxError, "parse error in\n\t#{equation}."
    end
    @flows << DerivativeFlow.new($1.intern, $2.strip, feedback)
  end
end

#euler(*equations) ⇒ Object 



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# File 'lib/redshift/syntax.rb', line 230

def euler(*equations)
  equations.each do |equation|
    unless equation =~ /^\s*(\w+)\s*'\s*=\s*(.+)/m
      raise SyntaxError, "parse error in\n\t#{equation}."
    end
    @flows << EulerDifferentialFlow.new($1.intern, $2.strip)
  end
end

#rk4(*equations) ⇒ Object Also known as: diff, differential 



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# File 'lib/redshift/syntax.rb', line 239

def rk4(*equations)
  equations.each do |equation|
    unless equation =~ /^\s*(\w+)\s*'\s*=\s*(.+)/m
      raise SyntaxError, "parse error in\n\t#{equation}."
    end
    @flows << RK4DifferentialFlow.new($1.intern, $2.strip)
  end
end