Function reference

From a QuadKey to a Simple Features data.frame and other conversions

Functions to convert a QuadKey to a sf POINT data.frame or sf POLYGON data.frame. Additionally, all the R functions described in the official documentation to convert QuadKeys to and from tiles, pixels and geographic coordinates are available.

quadkey_to_polygon()

Convert a QuadKey into a square polygon

quadkey_to_latlong()

Convert a string of Quadkey numbers to lat/long coordinates

quadkey_to_tileXY()

Convert a QuadKey into tile XY coordinates.

tileXY_to_pixelXY()

Convert tile XY coordinates into pixel XY coordinates

pixelXY_to_latlong()

Convert pixel XY coordinatess into lat/long coordinates.

latlong_to_quadkey()

Convert latitude/longitude coordinates into QuadKeys

latlong_to_pixelXY()

Convert lat/long coordinates to pixel XY coordinates

pixelXY_to_tileXY()

Convert pixel XY coordinates into tile XY coordinates

tileXY_to_quadkey()

Convert tile XY coordinates into a QuadKey.

mapsize()

Map size in pixels

mapscale()

Map scale (1 : N)

ground_res()

Ground resolution at a specified latitude and zoom level

Generating a Raster Image from Quadkey-Identified Data

Complete a grid of QuadKeys within a specified area and zoom level, and create a stars raster. You can also directly convert QuadKeys in a data.frame column into an sf POLYGON data.frame.

add_regular_polygon_grid()

Add the rows needed to complete a regular QuadKey polygon grid derived from the bounding box of the quadkey column of a data.frame.

create_stars_raster()

Create a stars raster

quadkey_df_to_polygon()

Convert data.frame with quadkey column to a sf POLYGON data.frame

create_qk_grid()

Create grid of QuadKeys for a particular zoom or level of detail.

get_qk_coord()

Get lat/long coordinates from the QuadKey

regular_qk_grid()

Convert a incomplete QuadKey sf POINT data.frame into a regular grid.

grid_to_polygon()

Convert a grid of QuadKeys to square polygons

Converting Facebook Mobility QuadKey-identified Datasets into Raster Files

Convert Facebook mobility data .csv files into .tif files by day and hour reported.

read_fb_mobility_files()

Read all the .csv files in a folder and format the data.

format_fb_data()

Format the Facebook mobility data

missing_combinations()

Detect dates and hours missing in filenames

get_regular_polygon_grid()

Get regular QuadKey polygon grid derived from the bounding box of the quadkey column of a data.frame.

polygon_to_raster()

Create and save raster images for different dates and times

apply_weekly_lag()

Apply a 7 day lag to the variable n_crisis

QuadKey Visualization App

Introduce a QuadKey visualization application enabling users to validate function outcomes.

qkmap_app()

Launch the Shiny App