[R] IP-Address

[David Huffer]

On Wednesday, June 17, 2009 3:33 PM, edwin<edwin7 at web.de> wrote:

 > Sorry, David has just told my that it was a mistake in my
 > example (Thanks David). I had a wrong idea. The right idea is:
 > make a ip range, when the number increament without an gap (and
 > with maximum number: 255, see example down).
 > In case my initial example would be:
 >  162.131.58.1
 >  162.131.58.2
 >  162.131.58.3
 >  162.131.58.4
 >  162.131.58.5
 >  162.131.58.6
 > The Range is: 162.131.58.1 - 162.131.58.6
 >  162.132.58.20
 > 162.132.58.20 (no range)
 >  162.252.20.21
 > 162.252.20.21 (no range)
 >  162.254.20.22
 > 162.254.20.22 (no range)
 >  163.253.7.23
 > 163.253.7.23 (no range)
 >  163.253.20.25
 > 163.253.20.25 (no range)
 >  161.138.45.226
 > 161.138.45.226 (no range)
 > Another example: [...]

Edwin, here's a function that does what you want. it probably
doesn't return the ranges the way you'll need them, but you can
play around with that part:

  iprange <- function ( x ) {
    ip.set  <- x
    ip <- do.call (
      rbind
      , lapply (
        ip.set
        , function ( x ) {
          as.numeric (
            unlist (
              strsplit (
                as.character ( x )
                , split = "."
                , fixed = TRUE
              )
            )
          )
        }
      )
    )
    ip <- cbind (
      ip
      , ip [ , 1 ] * 256^3
        + ip [ , 2 ] * 256^2
        + ip [ , 3 ] * 256
        + ip [ , 4 ]
    )
    ip.set <- ip.set [ order ( ip [ , 5] ) ]
    ip <- ip [ order ( ip [ , 5] ) , ]
    index.start <- which ( c ( -Inf , diff ( ip [ , 5] ) ) != 1 )
    index.end <- c ( index.start [-1] - 1 , tail ( index.start , 1 ) )
    iprange <- cbind (
      ip.set [ index.start ]
      , ifelse ( ip.set [ index.start ] == ip.set [ index.end ] , NA , ip.set [ index.end ] )
    )
    cat ("ip addresses:\n")
    cat (
      ip.set
      , sep = "\n"
    )
    cat ("\nip ranges:\n")
    cat (
      paste (
        ip.set [ index.start ]
        , ifelse (
          ip.set [ index.start ] == ip.set [ index.end ]
          , "(no range)"
          , paste (
            "to"
            , ip.set [ index.end ]
          )
        )
      )
      , sep = "\n"
    )
    invisible ( iprange )
  }

  test <- iprange (
    c (
      "162.131.58.1" , "163.253.7.23"
      , "162.131.58.2" , "163.253.20.25"
      , "162.131.58.3" , "161.138.45.226"
      , "162.131.58.4" , "169.131.58.1"
      , "162.131.58.5" , "169.131.58.2"
      , "162.131.58.6" , "169.132.58.3"
      , "162.132.58.20" , "250.131.58.4"
      , "162.252.20.21" , "250.131.58.5"
      , "162.254.20.22" , "250.131.58.7"
    )
  )

  test

HTH

--
 David
 
 -----------------------------------------------------
 David Huffer, Ph.D.               Senior Statistician
 CSOSA/Washington, DC           david.huffer at csosa.gov