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Convert a string of Quadkey numbers to lat/long coordinates

Source: R/qk_to_latlong_functions.R
quadkey_to_latlong.Rd

This function converts Quadkeys to latitude/longitude WGS-84 coordinates (in degrees). For further information, refer to the Microsoft Bing Maps Tile System documentation.

Usage

quadkey_to_latlong(quadkey_data)

Arguments

quadkey_data

A single QuadKey as a string or a vector with unique QuadKeys.

Value

A sf POINT data.frame with a quadkey column. The latitude/longitude coordinates represent the upper-left corner of the 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

See also

quadkey_to_tileXY

tileXY_to_pixelXY

pixelXY_to_latlong

Examples


quadkey_to_latlong(quadkey_data = "213")
#> Simple feature collection with 1 feature and 1 field
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: -45 ymin: -40.9799 xmax: -45 ymax: -40.9799
#> Geodetic CRS:  WGS 84
#>   quadkey             geometry
#> 1     213 POINT (-45 -40.9799)
quadkey_to_latlong(quadkey_data = c("213", "212", "210"))
#> Simple feature collection with 3 features and 1 field
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: -90 ymin: -40.9799 xmax: -45 ymax: 0
#> Geodetic CRS:  WGS 84
#>   quadkey             geometry
#> 3     210        POINT (-90 0)
#> 2     212 POINT (-90 -40.9799)
#> 1     213 POINT (-45 -40.9799)