52 lines
2.2 KiB
Markdown
52 lines
2.2 KiB
Markdown
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Use the `geo.groupByArea()` to group geo-temporal data by area and `geo.asTracks()`
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to group data into tracks or routes.
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- [Group data by area](#group-data-by-area)
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- [Group data into tracks or routes](#group-data-by-track-or-route)
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{{% note %}}
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For example results, use the [bird migration sample data](/influxdb/version/reference/sample-data/#bird-migration-sample-data)
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to populate the `sampleGeoData` variable in the queries below.
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{{% /note %}}
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### Group data by area
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Use the [`geo.groupByArea()` function](/flux/v0/stdlib/experimental/geo/groupbyarea/)
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to group geo-temporal data points by geographic area.
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Areas are determined by [S2 grid cells](https://s2geometry.io/devguide/s2cell_hierarchy.html#s2cellid-numbering)
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- Specify a new column to store the unique area identifier for each point with the `newColumn` parameter.
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- Specify the [S2 cell level](https://s2geometry.io/resources/s2cell_statistics)
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to use when calculating geographic areas with the `level` parameter.
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The following example uses the [sample bird migration data](/influxdb/version/query-data/flux/geo/#sample-data)
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to query data points within 200km of Cairo, Egypt and group them by geographic area:
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```js
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import "experimental/geo"
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sampleGeoData
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|> geo.filterRows(region: {lat: 30.04, lon: 31.23, radius: 200.0})
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|> geo.groupByArea(newColumn: "geoArea", level: 5)
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```
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### Group data by track or route
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Use [`geo.asTracks()` function](/flux/v0/stdlib/experimental/geo/astracks/)
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to group data points into tracks or routes and order them by time or other columns.
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Data must contain a unique identifier for each track. For example: `id` or `tid`.
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- Specify columns that uniquely identify each track or route with the `groupBy` parameter.
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- Specify which columns to sort by with the `sortBy` parameter. Default is `["_time"]`.
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The following example uses the [sample bird migration data](/influxdb/version/query-data/flux/geo/#sample-data)
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to query data points within 200km of Cairo, Egypt and group them into routes unique
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to each bird:
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```js
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import "experimental/geo"
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sampleGeoData
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|> geo.filterRows(region: {lat: 30.04, lon: 31.23, radius: 200.0})
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|> geo.asTracks(groupBy: ["id"], orderBy: ["_time"])
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```
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