diff --git a/doc/api/next_api_changes/removals/26852-OG.rst b/doc/api/next_api_changes/removals/26852-OG.rst index dc7d595f575f..08ad0105b70a 100644 --- a/doc/api/next_api_changes/removals/26852-OG.rst +++ b/doc/api/next_api_changes/removals/26852-OG.rst @@ -3,3 +3,10 @@ ... of the `.dates` module are removed without replacements. These were undocumented and not exported. + +Julian dates in Matplotlib were calculated from a Julian date epoch: ``jdate = +(date - np.datetime64(EPOCH)) / np.timedelta64(1, 'D')``. Conversely, a Julian +date was converted to datetime as ``date = np.timedelta64(int(jdate * 24 * +3600), 's') + np.datetime64(EPOCH)``. Matplotlib was using +``EPOCH='-4713-11-24T12:00'`` so that 2000-01-01 at 12:00 is 2_451_545.0 (see +`).