Perhaps it is not that surprising, given that
> mode(1L)
[1] "numeric"
and
> is.numeric(1L)
[1] TRUE
On the other hand, this is curious, to say the least:
> is.double(as(1L, "double"))
[1] FALSE
Here's the surprising behavior:
x <- 1L
xx <- as(x, "numeric")
class(xx)
## [1] "integer"
It occurs because the call to `as(x, "numeric")` dispatches the coerce
S4 method for the signature `c("integer", "numeric")`, whose body is
copied in below.
function (from, to = "numeric", strict = TRUE)
if (strict) {
class(from) <- "numeric"
from
} else from
This in turn does nothing, even when strict=TRUE, because that
assignment to class "numeric" has no effect:
x <- 10L
class(x) <- "numeric"
class(x)
[1] "integer"
Is this the desired behavior for `as(x, "numeric")`?
______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
