[Tagging] Default maxspeed unit on waterways
Hi, Currently, le wiki ([1]) suggests that maxspeed has to specify the unit knots when it's not km/h. But knot is the unit used worldwide on waterways. Why should we add something obvious on all waterway elements ? Could we suggest that the default unit for maxspeed on waterways is knot and the default km/h remains for highways and railways ? Pieren [1] http://wiki.openstreetmap.org/wiki/Key:maxspeed ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
km/h is derived, at least with an integer multiple of seconds, from SI units. mph and knots are not. I would prefer to keep one default unit per tag, consistently, everything else leads to confusion. Pieren wrote on 2014-10-29 14:14: Hi, Currently, le wiki ([1]) suggests that maxspeed has to specify the unit knots when it's not km/h. But knot is the unit used worldwide on waterways. Why should we add something obvious on all waterway elements ? Could we suggest that the default unit for maxspeed on waterways is knot and the default km/h remains for highways and railways ? Pieren [1] http://wiki.openstreetmap.org/wiki/Key:maxspeed ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
On Wed, Oct 29, 2014 at 2:52 PM, Tom Pfeifer t.pfei...@computer.org wrote: km/h is derived, at least with an integer multiple of seconds, from SI units. mph and knots are not. I would prefer to keep one default unit per tag, consistently, everything else leads to confusion. What is leading to confusion is to suggest that km/h is the default unit for waterway speed when knot is in use everywhere. Please think as a contributor, not as QA programmer or data consumer (it's easy to check if the speed limit belongs to a waterway or not). And The knot is a non-SI unit that is accepted for use with the SI (https://en.wikipedia.org/wiki/Knot_%28unit%29) Pieren ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
2014-10-29 14:07 GMT+00:00 Pieren pier...@gmail.com: On Wed, Oct 29, 2014 at 2:52 PM, Tom Pfeifer t.pfei...@computer.org wrote: km/h is derived, at least with an integer multiple of seconds, from SI units. mph and knots are not. I would prefer to keep one default unit per tag, consistently, everything else leads to confusion. What is leading to confusion is to suggest that km/h is the default unit for waterway speed when knot is in use everywhere. Pieren, is there an example of confusion actually being caused? Please think as a contributor, not as QA programmer or data consumer (it's easy to check if the speed limit belongs to a waterway or not). It's easy to think up potential for confusion whichever way we go on this. Thinking as a contributor, the editing interfaces should make it clear which units the user is stating/implying - as iD does, for example. I definitely sympathise with Tom's reasoning for one unit per tag, so I'd suggest there would need to be a strong case for this mixed-units approach... Dan And The knot is a non-SI unit that is accepted for use with the SI (https://en.wikipedia.org/wiki/Knot_%28unit%29) Pieren ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
On 29/10/2014 14:12, Ilpo Järvinen wrote: I don't know about other countries, but here in Finland the water maxspeed signage is in km/h although knot is used for almost everything else. In UK waterways, both MPH and knots are used. Usually MPH on canals and knots on rivers, though even this can depend on who the navigation authority is and how far back in history their statutes were written. ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
On Wed, Oct 29, 2014 at 3:47 PM, Malcolm Herring malcolm.herr...@btinternet.com wrote: On 29/10/2014 14:12, Ilpo Järvinen wrote: I don't know about other countries, but here in Finland the water maxspeed signage is in km/h although knot is used for almost everything else. In UK waterways, both MPH and knots are used. Usually MPH on canals and knots on rivers, though even this can depend on who the navigation authority is and how far back in history their statutes were written. Okay, if the unit is not generalized, then my idea doesn't make sens. Sorry for the noise. Pieren ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
On 10/29/14 10:47 AM, Malcolm Herring wrote: On 29/10/2014 14:12, Ilpo Järvinen wrote: I don't know about other countries, but here in Finland the water maxspeed signage is in km/h although knot is used for almost everything else. In UK waterways, both MPH and knots are used. Usually MPH on canals and knots on rivers, though even this can depend on who the navigation authority is and how far back in history their statutes were written. i understand where this is coming from, but i think we need to stick to a single units default for a given tag, and those should probably be in SI units. it's not exactly killing me to have to add mph when i tag maxspeed in the US. richard -- rwe...@averillpark.net Averill Park Networking - GIS IT Consulting OpenStreetMap - PostgreSQL - Linux Java - Web Applications - Search ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
On Wed, Oct 29, 2014 at 02:47:48PM +, Malcolm Herring wrote: On 29/10/2014 14:12, Ilpo Järvinen wrote: I don't know about other countries, but here in Finland the water maxspeed signage is in km/h although knot is used for almost everything else. In UK waterways, both MPH and knots are used. Usually MPH on canals and knots on rivers, though even this can depend on who the navigation authority is and how far back in history their statutes were written. ouch. Luckily we don't map anything in UK vs US gallons or UK vs US barrels or tons.. or do we? Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
On 29/10/2014 19:48, Richard Z. wrote: ouch. Luckily we don't map anything in UK vs US gallons or UK vs US barrels or tons.. or do we? US tons, certainly (and it has caught mappers out in the past when they've been looking for rogue values to correct). The UK uses (generally) metric measures for maxweights, a combination of both UK and metric for heights, and UK motorways have distances on signs in miles and what people from the USA would call mile markers in kilometers. Confused, you will be... Cheers, Andy ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] Default maxspeed unit on waterways
On Wed, Oct 29, 2014 at 8:14 AM, Pieren pier...@gmail.com wrote: Hi, Currently, le wiki ([1]) suggests that maxspeed has to specify the unit knots when it's not km/h. But knot is the unit used worldwide on waterways. Why should we add something obvious on all waterway elements? Except it totally isn't, especially inland, where countries often use the same units as on land. Even though the Columbia River's rivermarks are denominated in nautical miles upstream of the Columbia Bar (the area roughly from the end of the jetties into the Pacific Ocean at it's delta to roughly once you get past the riprap jetty that US 101 travels three miles into the Columbia River on before rising over the last mile on the Astoria-Megler Bridge), once you get past the Astoria Port of Entry area for foreign ships entering inland waters, speeds posted on buoys changes from knots to MPH. Could we suggest that the default unit for maxspeed on waterways is knot and the default km/h remains for highways and railways ? Yeah, how about no, let's keep maxspeed the default on km/h for the sake of the vast majority of elements that use maxspeed as a legal restriction. ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
