new — Creates a new IntervalYM object
IntervalYM.new(value, yearprecision)
#new creates a new IntervalYM object. With no arguments, the interval is set to zero. If value is specified, it must be a String, Fixnum, Bignum, Float or Ruby9i::Number. If it is one of the numeric types, it is used as a number of years. If yearprecision is specified, the corresponding instance variable is set.