On Jan 25, 2015, at 9:57 PM, Warner Losh <[email protected]> wrote:
>> On Jan 25, 2015, at 6:15 PM, G Ashton <[email protected]> wrote:
>>
>> Rob Seaman also wrote:
>>> Leap seconds are introduced at midnight UTC, not when TAI modulo 86400
>>> equals zero.
>>
>> I would think that midnight UTC is the instant when the UTC time becomes
>> 00:00:00. I would call the introduced second the one that began at 11:59:60
>> and ended one second later at 00:00:00.
>
> The second half of what Rob said is correct for at least some tens of
> thousands
> of years. :). Leap seconds are introduced just before midnight UTC, and are
> properly part of the last day of the month, not the first day of the
> following month.
>
> Warner
"At midnight" is a flexible enough phrase to also handle a second that
*finishes* being introduced at the stroke of midnight :-) The separation
between one day and the next is a half open interval - whether on the left or
the right was not the issue being discussed at the time. In image processing
coordinates might apply to the left, right or middle of the pixel. Etc and so
forth. I defer to Steve on all issues of the historical record.
In any event I've updated the leap indexing as previously discussed.
Have also started experimenting with DUT1 encoding, which is some amalgam of
the other three bulletins (predictions versus retroactive computations versus
severely rounded values on uneven calendar gridding). At any rate the 5
decimal places from Bulletin A fit neatly into a 20-bit int as at the bottom.
The idea would be to index into the entries via the explicit YYYYMM in the
name. One might imagine interpolating (linear, spline, whatever) between dates.
Rob
--
bulletin-c.leapsec.com -> 250.10.36.152 -> OK 2015 7 36 1 (1, 0)
latest.leapsec.com -> 250.10.36.152 -> OK 2015 7 36 1 (1, 0)
previous.leapsec.com -> 249.230.35.254 -> OK 2012 7 35 1 (1, 0)
first.leapsec.com -> 248.6.11.133 -> OK 1972 7 11 1 (1, 0)
origin.leapsec.com -> 248.0.10.245 -> OK 1972 1 10 1 (1, 0)
leap0.leapsec.com -> 248.0.10.245 -> OK 1972 1 10 1 (1, 0)
leap1.leapsec.com -> 248.6.11.133 -> OK 1972 7 11 1 (1, 0)
leap2.leapsec.com -> 248.12.12.208 -> OK 1973 1 12 1 (1, 0)
leap3.leapsec.com -> 248.24.13.158 -> OK 1974 1 13 1 (1, 0)
leap4.leapsec.com -> 248.36.14.76 -> OK 1975 1 14 1 (1, 0)
leap5.leapsec.com -> 248.48.15.2 -> OK 1976 1 15 1 (1, 0)
leap6.leapsec.com -> 248.60.16.129 -> OK 1977 1 16 1 (1, 0)
leap7.leapsec.com -> 248.72.17.6 -> OK 1978 1 17 1 (1, 0)
leap8.leapsec.com -> 248.84.18.147 -> OK 1979 1 18 1 (1, 0)
leap9.leapsec.com -> 248.96.19.154 -> OK 1980 1 19 1 (1, 0)
leap10.leapsec.com -> 248.114.20.85 -> OK 1981 7 20 1 (1, 0)
leap11.leapsec.com -> 248.126.21.129 -> OK 1982 7 21 1 (1, 0)
leap12.leapsec.com -> 248.138.22.40 -> OK 1983 7 22 1 (1, 0)
leap13.leapsec.com -> 248.162.23.128 -> OK 1985 7 23 1 (1, 0)
leap14.leapsec.com -> 248.192.24.127 -> OK 1988 1 24 1 (1, 0)
leap15.leapsec.com -> 248.216.25.124 -> OK 1990 1 25 1 (1, 0)
leap16.leapsec.com -> 248.228.26.174 -> OK 1991 1 26 1 (1, 0)
leap17.leapsec.com -> 248.246.27.9 -> OK 1992 7 27 1 (1, 0)
leap18.leapsec.com -> 249.2.28.21 -> OK 1993 7 28 1 (1, 0)
leap19.leapsec.com -> 249.14.29.193 -> OK 1994 7 29 1 (1, 0)
leap20.leapsec.com -> 249.32.30.45 -> OK 1996 1 30 1 (1, 0)
leap21.leapsec.com -> 249.50.31.138 -> OK 1997 7 31 1 (1, 0)
leap22.leapsec.com -> 249.68.32.220 -> OK 1999 1 32 1 (1, 0)
leap23.leapsec.com -> 249.152.33.233 -> OK 2006 1 33 1 (1, 0)
leap24.leapsec.com -> 249.188.34.161 -> OK 2009 1 34 1 (1, 0)
leap25.leapsec.com -> 249.230.35.254 -> OK 2012 7 35 1 (1, 0)
leap26.leapsec.com -> 250.10.36.152 -> OK 2015 7 36 1 (1, 0)
leap27.leapsec.com -> 92.242.140.2 -> CLASS ERR
dut1.201501.leapsec.com -> 240.210.218.53 -> -46022 -> -0.460220
seconds
dut1.201502.leapsec.com -> 240.198.80.149 -> -49232 -> -0.492320
seconds
dut1.201503.leapsec.com -> 240.184.18.42 -> -52878 -> -0.528780
seconds
dut1.201504.leapsec.com -> 240.166.142.108 -> -57362 -> -0.573620
seconds
dut1.201505.leapsec.com -> 240.150.39.208 -> -61561 -> -0.615610
seconds
dut1.201506.leapsec.com -> 240.137.158.247 -> -64770 -> -0.647700
seconds
dut1.201507.leapsec.com -> 242.10.187.39 -> 33819 -> 0.338190
seconds
dut1.201508.leapsec.com -> 242.9.149.181 -> 33525 -> 0.335250
seconds
dut1.201509.leapsec.com -> 242.2.114.186 -> 31698 -> 0.316980
seconds
dut1.201510.leapsec.com -> 241.245.33.186 -> 28289 -> 0.282890
seconds
dut1.201511.leapsec.com -> 241.227.208.63 -> 23856 -> 0.238560
seconds
dut1.201512.leapsec.com -> 241.213.32.100 -> 20096 -> 0.200960
seconds
dut1.201601.leapsec.com -> 241.201.93.90 -> 17085 -> 0.170850
seconds
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