Reorganizing data from 3 rows to 1

Question

I need to reorganize data from a csv file that contains mostly repeating data. I have the data imported into R in a dataframe but I am having trouble with the following:

ID   Language  Author   Keyword
12   eng       Rob      COLOR=Red
12   eng       Rob      SIZE=Large
12   eng       Rob      DD=1
15   eng       John     COLOR=Red
15   eng       John     SIZE=Medium
15   eng       John     DD=2

What I need to do is transform this into a row with each keyword in a separate column

ID   Language  Author  COLOR  SIZE      DD
12   eng       Rob     Red    Large     1

Any ideas?

Answer 1

Using the reshape2 package this is straightforward:

With tt defined as in Gary's answer

library("reshape2")

tt <- cbind(tt, colsplit(tt$Keyword, "=", c("Name", "Value")))
tt_new <- dcast(tt, ID + Language + Author ~ Name, value.var="Value")

which gives

> tt_new
  ID Language Author COLOR DD   SIZE
1 12      eng    Rob   Red  1  Large
2 15      eng   John   Red  2 Medium