Affects Version/s: ODF 1.2
Fix Version/s: ODF 1.4
Email from Mike Kaganski, 15 September 2020 reads:
As mentioned in , there is a problem in the OASIS OpenFormula standard (as of v.1.3 ). The spreadsheet functions YEAR, MONTH, DAY, HOUR, MINUTE are defined in such a way that for any given value of time, they discard fractions of respective time part: e.g., MINUTE would only return whole number of minutes contained in the parameter, discarding any fraction of a minute, no matter how close it is to 1. On the other hand, spreadsheet function SECOND is defined to round the number of seconds in minute fraction, thus it may return a number that is greater by 1 compared to the whole number of seconds actually contained in the minute fraction.
Furthermore, SECOND is defined to return 0 through 59 (never 60), but to use formula equivalent to ROUND(MinuteFraction * 60). Here is the first minor inconsistency: ROUND(MinuteFraction * 60) results in numbers 0 through 60, not through 59.
It is impossible to modify the definition of SECOND to return 0 through 60, because it would then become inconsistent with other spreadsheet software, introducing major interoperability problems. Correcting the equivalent formula to result in 0 through 59, like "MOD(ROUND(MinuteFraction * 60), 60)", brings us to the next inconsistency:
ÂÂÂ For all values of TimeParam T which have (MinuteFraction * 60) between 59.5 and 60.0, the set of functions:
Â ÂÂ ÂÂ =YEAR(T) &"
"& MONTH(T) &""& DAY(T) &" "& HOUR(T) &":"& MINUTE(T) &":"& SECOND(T)
ÂÂÂ results in an ISO date-time string that is off by ~1 minute (actually, exactly by value of (MinuteFraction * 60) seconds).
This happens because value returned by SECOND will be 0 (zero), as if the next minute has already started, while all other functions return values of the minute, hour, day, ... that are still active for T.
For instance, for T corresponding for 2020-09-15 15:23:59.60, the result of the mentioned formula would be "2020-9-15 15:23:0".
It is impossible to change definition of SECOND to discard fraction of a second (for consistency with other functions), because then it would again be inconsistent with other spreadsheet software. So the only solution is to re-define the other functions to be consistent with (improved) SECOND definition, like this:
ÂÂÂ * Proposed improvement for SECOND(TimeParam T): Second=MOD(ROUND(T*86400);60)
ÂÂÂ * Proposed change for MINUTE(TimeParam T): Minute=(MOD(ROUND(T*86400);3600)-SECOND(T))/60
ÂÂÂ ... etc.
This would not only make the functions consistent within the standard, but also with other spreadsheet software.