Full_Name: Sundar Dorai-Raj
Version: 1.7.1
OS: Windows 2000
Submission from: (NULL) (4.18.65.62)
Hi all,
I just discovered a problem when merging two data.frames which don't have
any
columns in common and when one (or both) of the data.frames is a single column.
E.g.
x <- data.frame(x = 1:5, y = letters[1:5])
y <- data.frame(z = 1:2)
z <- merge(x, y)
The result z is as expected, but the resulting names of z are not right.
I've
tracked it down to following the line in merge.data.frame:
if (l.b == 0) {
ij <- expand.grid(1:nx, 1:ny)
res <- cbind(x[ij[, 1], ], y[ij[, 2], ]) # <---
}
Changing this line to:
res <- cbind(x[ij[, 1], , drop = FALSE], y[ij[, 2], , drop = FALSE])
resolves the problem.