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Hello,
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<div>What is a good way to determine the temporal intersection of a tgeompoint and a</div>
<div>geometry with a time period?</div>
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<div>(This is similar to the the issue that I mentioned in the note that</div>
<div>vicky_at_georepublic.de posted on Jun 13, but now using a linestring instead of</div>
<div>a polygon).</div>
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<div>In air traffic control, there is often a need to establish a line-in-space for</div>
<div>a specific time period, and then identify the aircraft that crossed it during</div>
<div>that time period. (What aircraft crossed the boundary between these two air</div>
<div>traffic control regions between 1300z and 1500z for every day last week? How</div>
<div>does it compare to the number of aircraft that crossed that same boundary</div>
<div>between 1500z and 1700z?)</div>
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<div>How can the tintersects(tgeompoint, geometry) be combined with the</div>
<div>atPeriod(tgeompoint, period) to find out if the crossing happened</div>
<div>"when the linestring was active"?</div>
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<div>Is there a better way than using:</div>
<div> SELECT</div>
<div> tintersects(flown_path, boundary) as crossing_point,<br>
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<div> upper(period(atValue(tintersects(flown_path, boundary), TRUE))) as crossing_time<br>
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<div>to get all geospatial intersections (with the times), then following that with:</div>
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<div>WHERE crossing_time >= to_timestamp(interval_start, 'YYYY-MM-DD HH24:MI')</div>
<div> AND crossing_time <= to_timestamp(interval_end, 'YYYY-MM-DD HH24:MI')</div>
<div> AND tintersects(flown_path, boundary) is not null</div>
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<div>Thank you,</div>
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<div>Wendell</div>
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