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I converted some GPS point data to LineStrings and I am sometimes getting these jagged jumps in coordinates. I am pretty sure my data is correct, this anomaly is just to perfect to be wrong...

Anyone seen this before and knows what is going on?

Detail:

jagged lines

Overview:

overview of the detail

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    looks like your software only supports a certain number of vertices (example adobe illustrator only supports 60,000 points and returns to the first point to close a polygon) – Mapperz Aug 23 '17 at 4:27
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    How surprising, bad GPS data. Could it have something to do with en.wikipedia.org/wiki/Restrictions_on_geographic_data_in_China, apparently you need special permission to map China en.nasg.gov.cn/article/Lawsandregulations/201312/… – Michael Stimson Aug 23 '17 at 4:55
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    are you sure you have the correct vertice order for your lines/geometries? 'cause it looks like your data covers the outline of an area (the polygonlike shape in the overview) and a line along the road (in that detail image)? could you just have mixed those two features together (e.g. for the creation of the polygon outline; imagine the last 100 or so points are a seperate feature for the road while the fist bunch describes the polygon)? – ThingumaBob Aug 23 '17 at 11:40
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    @ThingumaBob just checked the source data again, and found the culprit. The source data is not sanitized correctly like the documentation says it should be. In the source file /062/Trajectory/20080926000623.plt you can see the data starting to jump between two locations at approximately line 7000. – Stevan Aug 28 '17 at 8:26
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    @ThingumaBob but to get back to you, about the data not being usable. I disagree, according to the documentation, every file represents one user and one trajectory, so the data is not mixed up. Just these few exceptions that I encountered, that according to the documentation shouldn't be there. But overall the data set is very useful for creating LineStrings. Cheers! – Stevan Aug 28 '17 at 8:30
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To answer my own question. I found out that the dataset has some discrepancies in it. So far as I can tell its in the following two files. Therein you can see that at a certain point the data starts jumping between two different trajectories.

.../062/Trajectory/20080926000623.plt
.../062/Trajectory/20081003000004.plt

Although the documentation says the data has been properly sanitized, there remains some additional sanitizing to be done.

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