# Time#round in 1.9 **URL:** \ **Category:** Ruby\ **Created:** [August 30, 2010, 8:47pm UTC](https://www.ruby-forum.com/t/time-round-in-1-9/194129 "2010-08-30T20:47:17Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![tcsnide](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/eb8c5e/32.png) [@tcsnide](https://www.ruby-forum.com/u/tcsnide)\ **Post date:** [August 30, 2010, 8:47pm UTC](https://www.ruby-forum.com/t/time-round-in-1-9/194129/1 "2010-08-30T20:47:17Z")
Anyone know about Time#round in 1.9. Apparently it exists but it seems to do nothing but eat up cpu cycles. ruby-1.9.2-p0 \> t = Time.new =\> 2010-08-30 14:34:03 -0400 ruby-1.9.2-p0 \> t.round(100000) =\> 2010-08-30 14:34:03 -0400 ruby-1.9.2-p0 \> t.round(1000000) =\> 2010-08-30 14:34:03 -0400 ---
**Author:** ![tcsnide](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/eb8c5e/32.png) [@tcsnide](https://www.ruby-forum.com/u/tcsnide)\ **Post date:** [August 30, 2010, 9:14pm UTC](https://www.ruby-forum.com/t/time-round-in-1-9/194129/2 "2010-08-30T21:14:47Z")
On Mon, Aug 30, 2010 at 12:42 PM, Intransition [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Anyone know about Time#round in 1.9. Apparently it exists but it seems > to do nothing but eat up cpu cycles. > > ruby-1.9.2-p0 \> t = Time.new > =\> 2010-08-30 14:34:03 -0400 > ruby-1.9.2-p0 \> t.round(100000) > =\> 2010-08-30 14:34:03 -0400 > ruby-1.9.2-p0 \> t.round(1000000) > =\> 2010-08-30 14:34:03 -0400 A voice was heard to utter: “Use the source, Luke! Errr, uh, Trans. Oh, and the docs!” /\* - call-seq: - time.round([ndigits]) → new\_time - - Rounds sub seconds to a given precision in decimal digits (0 digits by default). - It returns a new time object. - _ndigits_ should be zero or positive integer. - - ``` require 'time' ``` - - ``` t = Time.utc(2010,3,30, 5,43,"25.123456789".to_r) ``` - ``` p t.iso8601(10) #=> "2010-03-30T05:43:25.1234567890Z" ``` - ``` p t.round.iso8601(10) #=> "2010-03-30T05:43:25.0000000000Z" ``` - ``` p t.round(0).iso8601(10) #=> "2010-03-30T05:43:25.0000000000Z" ``` - ``` p t.round(1).iso8601(10) #=> "2010-03-30T05:43:25.1000000000Z" ``` - ``` p t.round(2).iso8601(10) #=> "2010-03-30T05:43:25.1200000000Z" ``` - ``` p t.round(3).iso8601(10) #=> "2010-03-30T05:43:25.1230000000Z" ``` - ``` p t.round(4).iso8601(10) #=> "2010-03-30T05:43:25.1235000000Z" ``` - ``` p t.round(5).iso8601(10) #=> "2010-03-30T05:43:25.1234600000Z" ``` - ``` p t.round(6).iso8601(10) #=> "2010-03-30T05:43:25.1234570000Z" ``` - ``` p t.round(7).iso8601(10) #=> "2010-03-30T05:43:25.1234568000Z" ``` - ``` p t.round(8).iso8601(10) #=> "2010-03-30T05:43:25.1234567900Z" ``` - ``` p t.round(9).iso8601(10) #=> "2010-03-30T05:43:25.1234567890Z" ``` - ``` p t.round(10).iso8601(10) #=> "2010-03-30T05:43:25.1234567890Z" ``` - - ``` t = Time.utc(1999,12,31, 23,59,59) ``` - ``` p((t + 0.4).round.iso8601(3)) #=> "1999-12-31T23:59:59.000Z" ``` - ``` p((t + 0.49).round.iso8601(3)) #=> "1999-12-31T23:59:59.000Z" ``` - ``` p((t + 0.5).round.iso8601(3)) #=> "2000-01-01T00:00:00.000Z" ``` - ``` p((t + 1.4).round.iso8601(3)) #=> "2000-01-01T00:00:00.000Z" ``` - ``` p((t + 1.49).round.iso8601(3)) #=> "2000-01-01T00:00:00.000Z" ``` - ``` p((t + 1.5).round.iso8601(3)) #=> "2000-01-01T00:00:01.000Z" ``` - - ``` t = Time.utc(1999,12,31, 23,59,59) ``` - ``` p (t + 0.123456789).round(4).iso8601(6) #=> ``` “1999-12-31T23:59:59.123500Z” \*/ Below that is a short, simple to follow implementation. You are telling it to round to 100000 or 1000000 digits. That’s probably not what you mean? Kirk H. ---
**Author:** ![tcsnide](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/eb8c5e/32.png) [@tcsnide](https://www.ruby-forum.com/u/tcsnide)\ **Post date:** [August 30, 2010, 9:47pm UTC](https://www.ruby-forum.com/t/time-round-in-1-9/194129/3 "2010-08-30T21:47:00Z")
On Aug 30, 3:13 pm, Kirk H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > A voice was heard to utter: “Use the source, Luke! Errr, uh, Trans. > Oh, and the docs!” The docs would be nice, but ri has been broken for months[1] and I could not find any mention of the method online. But you are right I could have checked the source. > - > - > > ``` > p t.round(7).iso8601(10) #=> "2010-03-30T05:43:25.1234568000Z" > > ``` > > - > > ``` > p((t + 1.5).round.iso8601(3)) #=> "2000-01-01T00:00:01.000Z" > > ``` > > - > - > > ``` > t = Time.utc(1999,12,31, 23,59,59) > > ``` > > - > > ``` > p (t + 0.123456789).round(4).iso8601(6) #=> > > ``` > > “1999-12-31T23:59:59.123500Z” > \*/ > > Below that is a short, simple to follow implementation. You are > telling it to round to 100000 or 1000000 digits. That’s probably not > what you mean? I see, so it only rounds sub-seconds per digit. That’s too bad, Facets’ #round method could round to any second. I have to rename. Thanks. [1] /home/trans/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/rdoc/ri/ driver.rb:909:in `load_method': undefined method `[]’ for nil:NilClass (NoMethodError)