Keep Right/020 multiple nodes on the same spot

Message: There is more than one node in this spot. Offending node IDs: $1

There are multiple nodes on same spot. In case of roads, it means that roads are not connected and routing programs will fail to route on such intersection. In some cases this is caused by duplicate uploads from JOSM (if you cancel during upload and upload again). In other cases it is caused by incorrect imports from other databases.

Author's comment:

• In contrast to earlier implementations of this check there is no tolerance window any more. So only nodes on exactly the same coordinates are considered an error. People tend to add more and more detailed features so precision increased over time and nowadays any minimum allowed distance greater than zero may be too large.
• This check now respects the ele=* tag in one special case to avoid false positives: Consider multiple nodes on the same lat/lon coordinates but with different elevation. If (and only if) nodes on the same lat/lon coordinates have unique ele values then no error is raised. This can happen at towers for example.

Continent	World	Africa	America-Canada	America-Central	America-South	America-US	Asia	Australia-Oceania	Europe
20150907	8,253,451	306,333	391,038	57,314	31,940	1,963,221	863,911	2,693,570	1,946,123
20141230	8,574,667	270,344	356,494	21,964	155,424	2,162,859	1,098,383	2,535,399	1,973,800
20140423	7,047,882	113,464	358,923	22,618	74,145	2,095,751	756,606	1,190,519	2,435,856
20131003	7,658,393	212,368	223,840	25,376	83,063	2,201,125	786,055	1,247,947	2,878,619
20130710	7,545,706	151,363	212,694	20,817	63,709	2,231,719	820,260	1,175,531	2,869,613
20130116	6,823,398	111,546	332,304	20,133	66,119	2,305,347	937,639	75,133	2,975,177
20121112	5,752,714	101,821	317,815	21,527	85,984	2,342,881	678,282	59,994	2,144,409
20121015	4,685,026	114,705	322,638	21,437	91,523	2,374,398	661,720	48,889	1,049,715
20120926	4,373,338	101,375	317,260	24,960	82,083	2,366,374	689,881	33,255	758,149
20120917	4,346,838	131,479	131,497	144,614	84,017	2,342,540	559,030	152,939	712,809
20120913	4,335,829	131,549	130,026	145,101	84,984	2,342,751	558,557	150,912	704,072