The `Orange`

data frame has 35 rows and 3 columns of records of
the growth of orange trees.

`Orange`

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

containing the following columns:

- Tree
an ordered factor indicating the tree on which the measurement is made. The ordering is according to increasing maximum diameter.

- age
a numeric vector giving the age of the tree (days since 1968/12/31)

- circumference
a numeric vector of trunk circumferences (mm). This is probably “circumference at breast height”, a standard measurement in forestry.

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) coplot(circumference ~ age | Tree, data = Orange, show.given = FALSE) fm1 <- nls(circumference ~ SSlogis(age, Asym, xmid, scal), data = Orange, subset = Tree == 3) plot(circumference ~ age, data = Orange, subset = Tree == 3, xlab = "Tree age (days since 1968/12/31)", ylab = "Tree circumference (mm)", las = 1, main = "Orange tree data and fitted model (Tree 3 only)") age <- seq(0, 1600, length.out = 101) lines(age, predict(fm1, list(age = age))) # }