Ruby 1.9.2 リファレンスマニュアル > ライブラリ一覧 > 組み込みライブラリ > Timeクラス > subsec
subsec -> numberReturns just the fraction for <i>time</i>.
The result is possibly rational.
t = Time.now #=> 2009-03-26 22:33:12 +0900 "%10.9f" % t.to_f #=> "1238074392.940563917" t.subsec #=> (94056401/100000000)
The lowest digit of to_f and subsec is different because IEEE 754 double is not accurate enough to represent the rational. The accurate value is returned by subsec.