merge() multiple data frames (do.call ?)
- by Vincent
Hi everyone, here's my very simple question:
merge() only takes two data frames as input. I need to merge a series of data frames from a list, using the same keys for every merge operation. Given a list named "test", I want to do something like: do.call("merge", test). I could write some kind of loop, but I'm wondering if there's a standard or built-in way to do this more efficiently.
Any advice is appreciated. Thanks!
Here's a subset of the dataset in dput format (note that merging on country is trivial in this case, but that there are more countries in the original data):
test <-
list(structure(list(country = c("United States", "United States",
"United States", "United States", "United States"), NY.GNS.ICTR.GN.ZS = c(13.5054687,
14.7608697, 14.1115876, 13.3389063, 12.9048351), year = c(2007,
2006, 2005, 2004, 2003)), .Names = c("country", "NY.GNS.ICTR.GN.ZS",
"year"), row.names = c(NA, 5L), class = "data.frame"), structure(list(
country = c("United States", "United States", "United States",
"United States", "United States"), NE.TRD.GNFS.ZS = c(29.3459277,
28.352838, 26.9861939, 25.6231246, 23.6615328), year = c(2007,
2006, 2005, 2004, 2003)), .Names = c("country", "NE.TRD.GNFS.ZS",
"year"), row.names = c(NA, 5L), class = "data.frame"), structure(list(
country = c("United States", "United States", "United States",
"United States", "United States"), NY.GDP.MKTP.CD = c(1.37416e+13,
1.31165e+13, 1.23641e+13, 1.16309e+13, 1.0908e+13), year = c(2007,
2006, 2005, 2004, 2003)), .Names = c("country", "NY.GDP.MKTP.CD",
"year"), row.names = c(NA, 5L), class = "data.frame"))
