walkalytics (version 0.1.0)

isochrone_esri: Issue a walkalytics isochrone query

Description

isochrone_esri calls the walkalytics isochrone API which calculates the walking isochrone for a source location and returns a repsonse object that contains a base64-encoded gzipped Esri ASCII grid with walking times for every pixel.

Usage

isochrone_esri(x, y, epsg = 3857, max_min = 1000,
  key = "my_walkalytics_key")

Arguments

x

x-coordinate of the source location (coordinate system is WGS/84 Pseudo Mercator).

y

y-coordinate of the source location (coordinate system is WGS/84 Pseudo Mercator).

epsg

EPSG code for coordinate system of the x- and y-coordinate.

max_min

maximum number of minutes for the isochrone.

key

your walkalytics subscription key which provides access to the API.

Value

The response object from the request. Use esri_to_sgdf to convert the base64-encoded gzipped Esri ASCII grid to an object of class SpatialGridDataFrame-class. Use pixel_walktimes to directly extract walking times for every pixel.

Details

To get an API key, you need to register at https://dev.walkalytics.com/signin. With the free starter account, you can make up to 100 calls a week to the API.

References

Walkalytics API documentations

Examples

# NOT RUN {
isochrone_esri(x = 895815, y = 6004839, key = "abcd1234")
# }
# NOT RUN {
# }