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Convert latitude/longitude coordinates into QuadKeys

Source: R/latlong_to_qk_functions.R
latlong_to_quadkey.Rd

Converts a point from latitude/longitude WGS-84 coordinates (in degrees) into a Quadkey at a specified zoom level. For further information, refer to the Microsoft Bing Maps Tile System documentation.

Usage

latlong_to_quadkey(lat, lon, zoom)

Arguments

lat

Latitude of the point, in degrees.

lon

Longitude of the point, in degrees.

zoom

Zoom or level of detail, from 1 (lowest detail) to 23 (highest detail).

Value

A dataframe with latitude (lat), longitude (lon), zoom level (zoom) and the QuadKey as a string (quadkey).

Details

Converting latitude/longitude coordinates into a QuadKey and then back to latitude/longitude won't yield identical values, unless the initial latitude/longitude coordinates correspond to the upper-left Quadkey's pixel and tile XY coordinates at the same zoom level.

Understanding this distinction is crucial for the accurate use of these functions in coordinate conversions.

For a detailed explanation on how to use this and other similar quadkeyr functions, read the the vignette: https://fernandez-lab-wsu.github.io/quadkeyr/articles/quadkey_to_sf_conversion.html

References

https://learn.microsoft.com/en-us/bingmaps/articles/bing-maps-tile-system

Examples


latlong_to_quadkey(
  lat = 35.63051,
  lon = 139.69116,
  zoom = 20
)
#> Simple feature collection with 1 feature and 1 field
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: 139.6912 ymin: 35.63051 xmax: 139.6912 ymax: 35.63051
#> Geodetic CRS:  WGS 84
#>                quadkey                  geometry
#> 1 13300211230321211111 POINT (139.6912 35.63051)
latlong_to_quadkey(
  lat = c(-4, -25.33, -25.66),
  lon = c(-53, -60.33, -70.66),
  zoom = 4
)
#> Simple feature collection with 3 features and 1 field
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: -70.66 ymin: -25.66 xmax: -53 ymax: -4
#> Geodetic CRS:  WGS 84
#>   quadkey              geometry
#> 1    2101        POINT (-53 -4)
#> 2    2103 POINT (-60.33 -25.33)
#> 3    2102 POINT (-70.66 -25.66)