geo.groupByArea() function

geo.groupByArea() groups rows by geographic area.

Area sizes are determined by the specified level. Each geographic area is assigned a unique identifier (the S2 cell ID token) which is stored in the newColumn. Results are grouped by newColumn.

Function type signature

(
    <-tables: stream[{A with s2_cell_id: string, lon: float, lat: float}],
    level: int,
    newColumn: string,
    ?s2cellIDLevel: int,
) => stream[B] where B: Record

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Parameters

newColumn

({{< req >}}) Name of the new column for the unique identifier for each geographic area.

level

({{< req >}}) S2 Cell level used to determine the size of each geographic area.

s2cellIDLevel

S2 Cell level used in the s2_cell_id tag. Default is -1 (detects S2 cell level from the s2_cell_id tag).

tables

Input data. Default is piped-forward data (<-).

Examples

Group geotemporal data by geographic area

import "experimental/geo"

data
    |> geo.groupByArea(newColumn: "foo", level: 4)

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Input data

Output data

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