The `Loblolly`

data frame has 84 rows and 3 columns of records of
the growth of Loblolly pine trees.

`Loblolly`

An object of class
`c("nfnGroupedData", "nfGroupedData", "groupedData", "data.frame")`

containing the following columns:

- height
a numeric vector of tree heights (ft).

- age
a numeric vector of tree ages (yr).

- Seed
an ordered factor indicating the seed source for the tree. The ordering is according to increasing maximum height.

This dataset was originally part of package `nlme`

, and that has
methods (including for `[`

, `as.data.frame`

, `plot`

and
`print`

) for its grouped-data classes.

# NOT RUN { require(stats); require(graphics) plot(height ~ age, data = Loblolly, subset = Seed == 329, xlab = "Tree age (yr)", las = 1, ylab = "Tree height (ft)", main = "Loblolly data and fitted curve (Seed 329 only)") fm1 <- nls(height ~ SSasymp(age, Asym, R0, lrc), data = Loblolly, subset = Seed == 329) age <- seq(0, 30, length.out = 101) lines(age, predict(fm1, list(age = age))) # }