I'm trying to parse 1 column of a dataframe into 3 seperate columns

-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
project.org] On Behalf Of Joel Pulliam
Sent: Monday, January 14, 2013 4:30 PM
To: r-help at r-project.org
Cc: pulliamjs at gmail.com
Subject: [R] I'm trying to parse 1 column of a dataframe into 3
seperate columns

I have a factor called 'utm_medium' in the dataframe 'data'

str(data$utm_medium)

Factor w/ 396925 levels
"","affiliateID=&sessionID=0000821850667323ec6ae6cffd28f380&etag=",..:
366183 355880 357141 20908 357513 365348 368088 360827 31704 364767 ...



The data in this factor is delimited with '&'. I basically want the
affiliateID, sessionID and etag data separated. Ex.

data$utm_medium[1:10]

[1]
affiliateID=4f3ac4b695e7d&sessionID=993f4c447e68dfc36ed692223349f2e3&et
a
g=

[2]
affiliateID=4f3ac4b695e7d&sessionID=209dd9986ace55d50a450afeba62b78f&et
a
g=

[3]
affiliateID=4f3ac4b695e7d&sessionID=2efdb8e1e1f5ac9c0d5baec355c78f85&et
a
g=

[4] affiliateID=&sessionID=5a6ca9d41148f30ce694628427af7991&etag=


 [5]
affiliateID=4f3ac4b695e7d&sessionID=331fbcdf1f3d5e7bac0d92c12e19f63d&et
a
g=

[6]
affiliateID=4f3ac4b695e7d&sessionID=8fc27c8478e9bd30043ea4d3c7ddb29c&et
a
g=

[7]
affiliateID=4f3ac4b695e7d&sessionID=af467d480addffca43ffbdbce1edfdb4&et
a
g=

[8]
affiliateID=4f3ac4b695e7d&sessionID=598645e05a187ee63ff922a36360f021&et
a
g=

[9] affiliateID=&sessionID=8895e21d0842ed45063ba8328dc3bc61&etag=


[10]
affiliateID=4f3ac4b695e7d&sessionID=88ca2998c5a91b6efbece0c4f79caeb7&et
a
g=

396925 Levels:  ...
affiliateID=50bfbbbeed918&sessionID=5c49c142cbf1b149c6a4647d1a4fc97b&et
a
g=



I've parsed it via:

test <-as.character(data$utm_medium)

test <- strsplit(test, "&")



which results in a list, which I 'unlisted':

test2 <- unlist(test)



and then attempted to extract into separate vectors:

a <- vector(mode = "character", length = length(test2))

s <- vector(mode = "character", length = length(test2))

e <- vector(mode = "character", length = length(test2))

i <- 1

j <- 1



  for (i in 1:length(test2))

  {

    a[j] <- test2[i]

    s[j] <- test2[i+1]

    e[j] <- test2[i+2]

    i <- i + 3

    j <- j + 1

  }



This code runs, but I'm indexing it incorrectly and I can't figure out
why. I'll sleep on it tonight and probably figure it out, but I can't
help thinking that there's a much easier way to parse this data. Help!
Please!



joel




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