[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
thiemowmde added a comment. Sorry, I have to disagree. There may be a sweep spot where such a "formatting for display" is ok, but rounding "1.9+-1" to "2+-1" is clearly **wrong**, at least in my opinion. These two strings describe two completely different values. TASK DETAIL https://phabricator.wikimedia.org/T95425 REPLY HANDLER ACTIONS Reply to comment or attach files, or !close, !claim, !unsubscribe or !assign . EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: thiemowmde Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
daniel added a comment. They are two different intervals, sure. If you however consider the +/- as an uncertainty, they are "nearly" the same in the sense that the difference is insignificant. An uncertainty interval of +/-1 is the explicit statement that any difference <1 is insignificant. If you want the rounding to work differently, please file a separate ticket for that issue, and provide a specification of how you want it to work, and a rationale. Please consider that one of the main use cases is unit conversion: Per convention and common sense, we'd want 3ft (+-/1) to convert to 1m (+/-0.3048) not to 0.9144m (+/-0.3048). That latter would imply a precision that is not present in the original value. But in any case, let's keep the "data loss in round-trip" issue separate from the "rounding is evil" question. TASK DETAIL https://phabricator.wikimedia.org/T95425 REPLY HANDLER ACTIONS Reply to comment or attach files, or !close, !claim, !unsubscribe or !assign . EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: daniel Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
thiemowmde added a comment. Separate? How? I don't understand. A formatter that silently manipulates 1.5+-1 to 2+-1 does change the actual value by 66%. You can't argue that such a major data loss is insignificant. TASK DETAIL https://phabricator.wikimedia.org/T95425 REPLY HANDLER ACTIONS Reply to comment or attach files, or !close, !claim, !unsubscribe or !assign . EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: thiemowmde Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
daniel added a comment. @thiemowmde: i think this becomes a lot clearer when you think about your original value being in meter, and you are trying to display it in feet. The we must apply rounding based on the uncertainty, otherwise we would be introducing false precision. And if we do this for the case with conversion, we should also do it without conversion, for consistency. TASK DETAIL https://phabricator.wikimedia.org/T95425 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: daniel Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
thiemowmde added a comment. The rounding is wrong no matter what. 24+/-10 becomes 20+/-10 with the current formatting. This is not even remotely the same value. TASK DETAIL https://phabricator.wikimedia.org/T95425 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: thiemowmde Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
thiemowmde added a comment. 15+/-1 feet becomes 5+/-1 meter which becomes 16+/-1 feet. The "before" and "after" values are not there to mark "irrelevant" digits. There is no such thing as an "irrelevant" digit in Quantity values. We do have this in Time, but not in Quantity. TASK DETAIL https://phabricator.wikimedia.org/T95425 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: thiemowmde Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
daniel added a comment. What rounding would be correct then, and would also work with unit conversion? I agree that the current output is a bit odd when the uncertainty interval is included. 24+/-10 can be written as 20 (because we don't care about the 4), but I agree that writing it as 20+/-10 is somewhat odd. TASK DETAIL https://phabricator.wikimedia.org/T95425 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: daniel Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
thiemowmde added a comment. In https://phabricator.wikimedia.org/T95425#1353657, @daniel wrote: > 24+/-10 can be written as 20 (because we don't care about the 4) This is simply wrong. These are two completely distinct values. But I'm already repeating myself. TASK DETAIL https://phabricator.wikimedia.org/T95425 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: thiemowmde Cc: daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
Snipre added a subscriber: Snipre. Snipre added a comment. Writing 1.4+-1 means you can't have a precision of 0.4. To be able to write this thing correctly you have to adjust your uncertainty precision to 1.0 so 1.4 +- 1.0 is correct. TASK DETAIL https://phabricator.wikimedia.org/T95425 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: Snipre Cc: Snipre, mgrabovsky, daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
[Wikidata-bugs] [Maniphest] [Commented On] T95425: Quantity rounding causes data loss when editing
thiemowmde added a comment. I'm sorry, but I do not understand that example at all. Where does a "0.4" come from in your example? 1.4+-1 is internally stored as { amount: 1.4, before: 0.4, after: 2.4 }. This is, when displayed via the formatter, displayed and later parsed as 1.4+-1. You can say "precision is 1", but keep in mind that we do not store it that way. In reality there is no precision. Displaying 1.4+-1.0 instead doesn't change anything. You can say: the precision value can't have a precision. TASK DETAIL https://phabricator.wikimedia.org/T95425 EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: thiemowmde Cc: Snipre, mgrabovsky, daniel, thiemowmde, Aklapper, Wikidata-bugs, aude ___ Wikidata-bugs mailing list Wikidata-bugs@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs