Displaying 1 result from an estimated 1 matches for "mylightweightdataframe".
2004 Nov 26
2
Lightweight data frame class
...ould
inherit from "list" and implement [,], [,]<- operators. It would also
implement the "rownames" function that would return seq(nrow(x)), etc.
It should also implement as.data.frame to avoid the overhead of
conversion to a full-blown data.frame in calls like lm(y ~ x,
data=myLightweightDataframe).
Has anyone thought of this? Can you see any potential problems?
Thanks,
Vadim
P.S. These are the timing results comparing data.frame operations to
those of lists
# make a 1e6 * 5 list
> system.time(x <- lapply(seq(5), function(x) rnorm(1e6)))
[1] 4.46 0.10 4.57 0.00 0.00
# conver...