This famous (Fisher's or Anderson's) iris data set gives the measurements in centimeters of the variables sepal length and width and petal length and width, respectively, for 50 flowers from each of 3 species of iris. The species are Iris setosa, versicolor, and virginica.
iris is a data frame with 150 cases (rows) and 5 variables
iris3 gives the same data arranged as a 3-dimensional array
of size 50 by 4 by 3, as represented by S-PLUS. The first dimension
gives the case number within the species subsample, the second the
measurements with names
Petal L., and
Petal W., and the third the species.
Fisher, R. A. (1936) The use of multiple measurements in taxonomic problems. Annals of Eugenics, 7, Part II, 179–188.
The data were collected by Anderson, Edgar (1935). The irises of the Gaspe Peninsula, Bulletin of the American Iris Society, 59, 2–5.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988)
The New S Language.
Wadsworth & Brooks/Cole. (has
matplot some examples of which use
dni3 <- dimnames(iris3) ii <- data.frame(matrix(aperm(iris3, c(1,3,2)), ncol = 4, dimnames = list(NULL, sub(" L.",".Length", sub(" W.",".Width", dni3[])))), Species = gl(3, 50, labels = sub("S", "s", sub("V", "v", dni3[])))) all.equal(ii, iris) # TRUE