stack_list: Stack a List of DataFrame-like Objects
In Kmisc: Kevin Miscellaneous

Description Usage Arguments Details Examples

Function for stacking a list, where each component of the list is a data.frame containing potentially differing number of rows, but the same number of columns, and with all columns of equivalent class.

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stack_list(list, name = "row_names", make_row_names = typeof(attr(list[[1]],
  "row.names")) == "character", keep_list_index = TRUE,
  index_name = "list_index", coerce_factors = TRUE)

`list`	a list of data frames, or a list of lists with each element of the same length.
`name`	a name to assign to the column of row names generated.
`make_row_names`	boolean. add a column built from the row names? Defaults to `TRUE` only if the row names are of type `character`.
`keep_list_index`	boolean; if `TRUE` we include a vector that indicates which list a particular entry came from.
`index_name`	a name to assign to the column of indices.
`coerce_factors`	boolean; if `TRUE`, we convert factors to their character representation; otherwise, we take the internal integer representation.

When stacking data.frames with row names, they are passed into a column called row_names to protect from problems with non-unique row names, and also to avoid appending numbers onto these row names as well.

Note that information on factors is lost by default; they will be converted either to characters or their internal integer representations.

x <- data.frame( x=c(1, 2, 3), y=letters[1:3], z=rnorm(3), stringsAsFactors=FALSE )
rownames(x) <- c("apple", "banana", "cherry")
y <- data.frame( x=c(4, 5, 6), y=LETTERS[1:3], z=runif(3), stringsAsFactors=FALSE )
rownames(y) <- c("date", "eggplant", "fig")
tmp1 <- stack_list( list(x, y) )
tmp2 <- do.call( rbind, list(x, y) )
rownames(tmp2) <- 1:nrow(tmp2)
all.equal( tmp1[,1:3], tmp2 )