5 ms·

I find them a lot more human-friendly, but I guess that's subjective. The example from the wiki page you linked: MGRS: 4QFJ12345678 Plus Code: 835M+Q7 Honolul

I find them a lot more human-friendly, but I guess that's subjective. The example from the wiki page you linked: MGRS: 4QFJ12345678 Plus Code: 835M+Q7 Honolulu

dzhiurgis 8y ago
Wait a second. So 835M+Q7 is not a full identifier? You need to specify city too? Ain't that gonna cause problems?
- arghwhat 8y ago
  It's a referenced plus-code, which "saves" 4 digits. Instead of being a true location like the full plus code, coordinates, or MGRS, a referenced plus-code requires a referenced location to resolve (think "124 meters north of the postal office"), and the precision becomes entirely dependent on the precision of the services used to resolve the reference location (i.e. Google Maps might consider the exact location for "Honolulu" to be somewhere else on the island of Honolulu than Bing Maps).
  - detaro 8y ago
    No, they do not work relative to a point. You replace the first 4 digits of the code (the area code) with a location name that's clearly in the area, the following digits stay the same. The name resolution of the location can be off by kilometers and it still works.
    - arghwhat 8y ago
      While you are correct in stating that the point is only used to resolve the area, you conclusion is off by kilometers (he he he). When using a point to resolve a 4-digit code (1x1 degree, approx 100x100km), it is true that anywhere within the same 4-digit-equivalent area will result in the same location. However, while this improves the average case compared to point referencing, it makes the worst case absolutely horrendous: You'll end up referring to a wrong long/lat degree, meaning an error of over 100km! The closer you are to the edge of a lat/long degree, the more vulnerable you are. If your location is, say, 10 meters from the edge, then 10 meters geocoding imprecision is all it takes to cause a >100km error. Which is exactly why the plus-code readme says the following, as I have quoted before: > If the reference location is derived from a town or city name, it is dependent on the accuracy of the geocoding service. Although one service may place "Zurich" close to the Google office, another may move it by a hundred meters or more, and this could be enough to prevent the original code being recovered. Rather than a large city size feature to generate the reference location, it is better to use smaller, neighbourhood features, that will not have as much variation in their geocode results. In order for the reference system to work, references must either be close to the center of a lat/long degree (which allows great error margins on geocoding), or use points which have consistently high precision. Neither case result in memorable reference codes like "XYZ Honolulu", so just using the extra 4 digits is the only sensible choice.
arghwhat 8y ago
That's only a partial plus-code, though, which relies on external positioning of Honolulu. The full plus-code is 4 digits longer, and with the plus itself, it's 11 chars vs. 12 for MGRS at 10m precision (14 for 1m, which is more than plus-codes can do). If MGRS was too long, it could simply get a new encoding and be done with, or add the abbreviation system. Also, that particular plus-code you used as example is not recommended. Reference points should be small features that will have low geocoding variance. Larger points like cities, or here whole islands, as there can be very large variance to the exact location derived from the name (i.e. the pinpoint location Google Maps finds you when you just search for Honolulu). From the README: > Rather than a large city size feature to generate the reference location, it is better to use smaller, neighbourhood features, that will not have as much variation in their geocode results.
- chronial 8y ago
  > That's only a partial plus-code, though, which relies on external positioning of Honolulu. Yes, a concept that is very human-friendly. > Also, that particular plus-code you used as example is not recommended. Reference points should be small features that will have low geocoding variance. Larger points like cities, or here whole islands, as there can be very large variance to the exact location derived from the name (i.e. the pinpoint location Google Maps finds you when you just search for Honolulu). You should take that up with the google devs I guess. The code I gave was generated by google maps.
  - arghwhat 8y ago
    > Yes, a concept that is very human-friendly. It's also entirely broken, rendering the system unusable if you expect sub-kilometer positioning across different geocoding providers. Whether something entirely defective is "human friendly" doesn't really matter. > You should take that up with the google devs I guess. The code I gave was generated by google maps. Not my responsibility. That they cannot even use it correctly as per their own docs themselves doesn't make for a good sales pitch. In fact, Google Maps cannot process plus codes using arbitrary reference locations, making use per the plus-code documentation impossible with it. To give an idea of why that plus code is borked: Honolulu @ Google Maps: 21.3069444,-157.8583333 Honolulu @ Bing Maps: 21.30493,-157.85788 The difference is around 300 meters, which results in an absolutely awful error margin, and I'd argue that this is very much one of the best-case scenarios. That's worse than if they had added 2 more characters to the plus code, and just removed the Honolulu part.
nabla9 8y ago
MGRS has variable precision just like Plus code. 4QFJ12345678 has precision 10 m. Example of plus code with comparable accuracy: 73F69J3M+VV 10 km accuracy in MGRS is just six letters: 4QFJ16 100 km accuracy is just 4 letters: 4QFJ
- chronial 8y ago
  The Plus code I gave as an example addresses a 14x14m square, Not 10 km.

I find them a lot more human-friendly, but I guess that's subjective. The example from the wiki page you linked: MGRS: 4QFJ12345678 Plus Code: 835M+Q7 Honolulu

dzhiurgis 8y ago

Wait a second. So 835M+Q7 is not a full identifier? You need to specify city too? Ain't that gonna cause problems?

arghwhat 8y ago
It's a referenced plus-code, which "saves" 4 digits. Instead of being a true location like the full plus code, coordinates, or MGRS, a referenced plus-code requires a referenced location to resolve (think "124 meters north of the postal office"), and the precision becomes entirely dependent on the precision of the services used to resolve the reference location (i.e. Google Maps might consider the exact location for "Honolulu" to be somewhere else on the island of Honolulu than Bing Maps).
- detaro 8y ago
  No, they do not work relative to a point. You replace the first 4 digits of the code (the area code) with a location name that's clearly in the area, the following digits stay the same. The name resolution of the location can be off by kilometers and it still works.
  - arghwhat 8y ago
    While you are correct in stating that the point is only used to resolve the area, you conclusion is off by kilometers (he he he). When using a point to resolve a 4-digit code (1x1 degree, approx 100x100km), it is true that anywhere within the same 4-digit-equivalent area will result in the same location. However, while this improves the average case compared to point referencing, it makes the worst case absolutely horrendous: You'll end up referring to a wrong long/lat degree, meaning an error of over 100km! The closer you are to the edge of a lat/long degree, the more vulnerable you are. If your location is, say, 10 meters from the edge, then 10 meters geocoding imprecision is all it takes to cause a >100km error. Which is exactly why the plus-code readme says the following, as I have quoted before: > If the reference location is derived from a town or city name, it is dependent on the accuracy of the geocoding service. Although one service may place "Zurich" close to the Google office, another may move it by a hundred meters or more, and this could be enough to prevent the original code being recovered. Rather than a large city size feature to generate the reference location, it is better to use smaller, neighbourhood features, that will not have as much variation in their geocode results. In order for the reference system to work, references must either be close to the center of a lat/long degree (which allows great error margins on geocoding), or use points which have consistently high precision. Neither case result in memorable reference codes like "XYZ Honolulu", so just using the extra 4 digits is the only sensible choice.

arghwhat 8y ago

That's only a partial plus-code, though, which relies on external positioning of Honolulu. The full plus-code is 4 digits longer, and with the plus itself, it's 11 chars vs. 12 for MGRS at 10m precision (14 for 1m, which is more than plus-codes can do). If MGRS was too long, it could simply get a new encoding and be done with, or add the abbreviation system. Also, that particular plus-code you used as example is not recommended. Reference points should be small features that will have low geocoding variance. Larger points like cities, or here whole islands, as there can be very large variance to the exact location derived from the name (i.e. the pinpoint location Google Maps finds you when you just search for Honolulu). From the README: > Rather than a large city size feature to generate the reference location, it is better to use smaller, neighbourhood features, that will not have as much variation in their geocode results.

chronial 8y ago
> That's only a partial plus-code, though, which relies on external positioning of Honolulu. Yes, a concept that is very human-friendly. > Also, that particular plus-code you used as example is not recommended. Reference points should be small features that will have low geocoding variance. Larger points like cities, or here whole islands, as there can be very large variance to the exact location derived from the name (i.e. the pinpoint location Google Maps finds you when you just search for Honolulu). You should take that up with the google devs I guess. The code I gave was generated by google maps.
- arghwhat 8y ago
  > Yes, a concept that is very human-friendly. It's also entirely broken, rendering the system unusable if you expect sub-kilometer positioning across different geocoding providers. Whether something entirely defective is "human friendly" doesn't really matter. > You should take that up with the google devs I guess. The code I gave was generated by google maps. Not my responsibility. That they cannot even use it correctly as per their own docs themselves doesn't make for a good sales pitch. In fact, Google Maps cannot process plus codes using arbitrary reference locations, making use per the plus-code documentation impossible with it. To give an idea of why that plus code is borked: Honolulu @ Google Maps: 21.3069444,-157.8583333 Honolulu @ Bing Maps: 21.30493,-157.85788 The difference is around 300 meters, which results in an absolutely awful error margin, and I'd argue that this is very much one of the best-case scenarios. That's worse than if they had added 2 more characters to the plus code, and just removed the Honolulu part.

nabla9 8y ago

MGRS has variable precision just like Plus code. 4QFJ12345678 has precision 10 m. Example of plus code with comparable accuracy: 73F69J3M+VV 10 km accuracy in MGRS is just six letters: 4QFJ16 100 km accuracy is just 4 letters: 4QFJ

chronial 8y ago
The Plus code I gave as an example addresses a 14x14m square, Not 10 km.