Group geo-temporal data

Use the geo.groupByArea() to group geo-temporal data by area and geo.asTracks() to group data into tracks or routes.

Group data by area

Use the geo.groupByArea() function to group geo-temporal data points by geographic area. Areas are determined by S2 grid cells

  • Specify a new column to store the unique area identifier for each point with the newColumn parameter.
  • Specify the S2 cell level to use when calculating geographic areas with the level parameter.

The following example uses the sample bird migration data to query data points within 200km of Cairo, Egypt and group them by geographic area:

  1. import "experimental/geo"
  2. sampleGeoData
  3. |> geo.filterRows(region: {lat: 30.04, lon: 31.23, radius: 200.0})
  4. |> geo.groupByArea(
  5. newColumn: "geoArea",
  6. level: 5
  7. )

Group data by track or route

Use geo.asTracks() function to group data points into tracks or routes and order them by time or other columns. Data must contain a unique identifier for each track. For example: id or tid.

  • Specify columns that uniquely identify each track or route with the groupBy parameter.
  • Specify which columns to sort by with the sortBy parameter. Default is ["_time"].

The following example uses the sample bird migration data to query data points within 200km of Cairo, Egypt and group them into routes unique to each bird:

  1. import "experimental/geo"
  2. sampleGeoData
  3. |> geo.filterRows(region: {lat: 30.04, lon: 31.23, radius: 200.0})
  4. |> geo.asTracks(
  5. groupBy: ["id"],
  6. sortBy: ["_time"]
  7. )

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