getNearestCRAN: Determine the nearest CRAN repository to your machine

In omegahat/GeoIP: Mapping IP addresses to physical locations

Determine the nearest CRAN repository to your machine

Description

This function computes the distance from a particular IP address/machine to the CRAN servers around the world. We can then use this to determine which server is closest or order the servers by proximity.

Usage

getNearestCRAN(ip = getHostIP(), mirrors = getCRANmirrors(),
               db = GeoIP_open(GeoIPData, GEOIP_STANDARD),
               serverLocations = getMirrorCoordinates(mirrors, db),
               byDist = FALSE)

Arguments

ip	the name or IP address of the machine of interest. By default, we use the current machine by querying its IP address via a Web site
mirrors	a data frame giving the information about the mirrors
db	a reference to the the GeoIP database
serverLocations	the locations of the CRAN mirrors of interest. This is a 2 x n matrix of longitude and latitude values
byDist	a logical value that controls whether to return the URL of the single closest CRAN server, or to return all of the servers ranked by proximity.

Details

This uses the GeoIP lite database to find the locations of the CRAN mirror servers.

Value

If byDist is FALSE, a character vector of length 1 giving the URL of the nearest server. The name of the single element is the description of the host, e.g. "University of California, Berkeley, CA".

If byDist is TRUE, the function returns a data frame containing all the information about the mirrors, ordered by closest server. So the first observation is the closest server this machine on which the command was run.

Author(s)

Duncan Temple Lang

References

GeoIP database from maxmind.com

See Also

GeoIP_record_by_addr and GeoIP_record_by_name

Examples

    # this is a snapshot of the mirrors taken as an example.
  data(oldMirrors)
  getNearestCRAN( mirrors = oldMirrors)

omegahat/GeoIP documentation built on Jan. 17, 2024, 6:22 p.m.