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12  
13  
14  # Purpose
15  
16  bulletind provides access to the IERS "Bulletin D" data to Python or to other
17  software that can process JSON data.
18  
19  "Bulletin D" is the publication that specifies the "DUT1 offset", the
20  difference between UTC and UT1, in units of 0.1 seconds. This is the value that
21  is ostensibly transmitted on various broadcast time signals, such as WWVB.
22  
23  The source of the data is
24  https://datacenter.iers.org/availableVersions.php?id=17 and covers April 1991
25  through the present. (the oldest Bulletin available is Number 21 issued
26  1991-04-22)
27  
28  
29  # Use
30  
31  bulletind includes bulletin data that was available the last time the software
32  was updated. Further updates can be downloaded to a per-user cache with
33  the `bulletind update` command or the `get_bulletin_d_data()` function.
34  Cached data can be printed as json with `bulletind json`, as tabular data with
35  `bulletind table`, or accessed with the `get_cached_bulletin_d_data()` function.
36  
37  The structure of the data is described by the `BulletinDInfo` type.
38  In json and tabular formats, dates are represented in the ISO standard format
39  YYYY-mm-dd.
40  
41  
42  # Development status
43  
44  This project was started as a way to prototype use of Bulletin D historical
45  data in wwvbgen. However, the quality of the historical data was not adequate
46  and the project is archived.