def erode( n = 3 )
      filter = Hornetseye::lazy( *( [ n ] * dimension ) ) { 0 }
      table( filter ) { |a,b| a }.diagonal { |m,x| m.minor x }
    end
def erode( n = 3 )
      filter = Hornetseye::lazy( *( [ n ] * dimension ) ) { 0 }
      table( filter ) { |a,b| a }.diagonal { |m,x| m.minor x }
    end
Erosion

 The erosion operation works on boolean as well as scalar values.

 @param [Integer] n Size of erosion operator.

 @return [Node] Result of operation.