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Error: 'Unable to interpret time or date' when entering specific dates from the year 1752

Technote (troubleshooting)


When you enter any dates on or between September 3, 1752 and September 13, 1752, Notes returns the following error message:

    "Unable to interpret Time or Date".

Resolving the problem

This is intended functionality.

The Notes/Domino code is designed to convert time/date calculations to and from Julian notation. This should not be confused with the Julian Calendar, which was instituted by Julius Caesar in 46 B.C. The Julian Calendar was built on the premise that the year was 365.25 days long and consisted of normal 365-day years interspersed with a 366-day leap year every fourth year. In 730 A.D., the Venerable Bede (an Anglo-Saxon monk) announced that the Julian year was 11 minutes, 14 seconds too long, building a cumulative error of about 1 day every 128 years. Nothing was done about this for 800 years.

By 1582, the error had grown to about 10 days. That year, Pope Gregory XIII decreed that Thursday, October 4, 1582 would be followed by Friday, October 15, thus correcting the calendar by 10 days. This began the Gregorian Calendar that is in use today. It uses a four-year cycle of leap years, and eliminates each leap year that occurs on three of every four centesimal years. Only centesimal years that are evenly divisible by 400 are leap years. Thus, the year 1600 was a 366-day leap year, but 1700, 1800, and 1900 were each 365 days. The year 2000 is also a leap year, as will be the year 2400.

The British and its possessions, including the American colonies, did not implement the Gregorian Calendar for another 170 years, by which time 11 days needed to be eliminated. The British decreed that September 2, 1752 would be followed by September 14, 1752.

Therefore, following the British implementation of the Gregorian Calendar, Notes does not recognize any dates between September 2 and September 14, 1752.

Notes stores all dates in a Julian notation. Astronomers use the Julian period because it is convenient to express long time intervals in days rather than months, weeks and years. This notation was devised in 1583 by Joseph Scaliger and named after his father, Julius. Scaliger had Julian Day #1 begin at noon, January 1, 4713 B.C. because it was the most recent coincidence of three major chronological cycles:

  • The 28-year solar cycle, after which dates in the Julian Calendar (December 6, for example) return to the same day of the week (Thursday)
  • The 19-year lunar cycle, after which the phases of the moon return to the same dates of the year
  • The 15-year indiction cycle, which the Romans used to regulate taxes

For example, 12 noon, March 17, 2005 is the beginning of Julian Day 2,453,447. Because it is typically a more useful practice with computers to compare dates using simple integers, Notes starts its Julian Days at midnight instead of noon.

Document information

More support for: IBM Notes

Software version: 6.0, 6.5, 7.0, 8.0, 8.5, 9.0

Operating system(s): Windows

Reference #: 1098816

Modified date: 05 October 2009

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