Generate travel time to nearest major city

Aggregates the high resolution travel time data to PRIO-GRID level

Usage

calc_traveltime(aggregation_function)

Arguments

aggregation_function

function used to aggregate values. Either an actual function, or for the following, their name: "mean", "max", "min", "median", "sum", "modal", "any", "all", "prod", "which.min", "which.max", "table", "sd" (sample standard deviation) and "std" (population standard deviation)

References

Nelson (2008). “Travel Time to Major Cities: A Global Map of Accessibility.” 2025-05-14.

Examples

# r <- calc_traveltime(aggregation_function = "median")