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A lot of these kind of coordinates have no right answer anyway. They are just an abstract approximation of something else, like a parcel, address, or place to
by 7952 7y ago
A lot of these kind of coordinates have no right answer anyway. They are just an abstract approximation of something else, like a parcel, address, or place to eat. And the lat/long will be completely useless for the vast majority of people.
In any serious application you should have known error values and probably be using a more appropriate projection. If you need to accurately locate something you need someone trained to do that with the right equipment.
- falcolas 7y agoThey aren't approximations; you can verify this yourself. Pull up Google Maps, pick an arbitrary spot with no businesses, and click. You will get at least 6 significant digit coordinates.
- 7952 7y agoNo, I meant that it is an approximation or the thing in the real world that it represents. For example, consider a restraunt. Should the point be at the entrance to the building, in the middle of the building, or maybe at the door round the back where mail is delivered, or at the centroid of the parcel. In order to actually use this excessive precision you would need to know that. In the examle cases the data is not formal enough for this to matter. It is an approximation of some real world thing and never meant to be used for highly precise work.
- falcolas 7y agoThen the coordinates presented should match that approximation. Anyone who has worked with plans knows that the number of significant digits presented on the plans has a meaning; it represents the margin of error. Online maps aren't respecting this, they're giving decimeter precision values on maps that are lucky if they're accurate to within meters, if not tens of meters. That's the problem.
- 7952 7y agoI think that makes sense on plans that are using a proper coordinate system and have sub-metre accuracy. But removing digits further just causes confusion. You are just using the grid ref as a proxy for something else, like a circle or square which represents the error. Except in these examples it doesn't matter. No one actually needs the data to be super accurate. The coordinate length is just a style thing. Are you working with plans that show decimal degrees at a specific precision? I am curious what domain that is.