Package 'inum'

Enumeration-type Representation of Vectors

Description

Elements of a vector are stored as a set of levels and an integer representing the enumeration.

Usage

enum(x)

Arguments

x	A vector. Currently, methods for factors, logicals, integers, and numeric vectors are implemented.

Details

The unique elements of x are stored as a levels attribute to an integer representing the enumeration. levels and nlevels methods are available. This is essentially the same as factor where the levels can be arbitrary vectors, not just characters.

Value

An object of class enum. A value of 0 encodes NA.

See Also

factor

Examples

(ex <- enum(x <- gl(2, 2)))
all.equal(levels(ex)[ex], x)

(ex <- enum(x <- rep(c(TRUE, FALSE), 2)))
all.equal(levels(ex)[ex], x)

(ex <- enum(x <- rep(1:5, 2)))
all.equal(levels(ex)[ex], x)

(ex <- enum(x <- rep(1:5 + .5, 2)))
all.equal(levels(ex)[ex], x)

(ex <- enum(x <- c(NA, rep(1:5 + .5, 2))))
all.equal(c(NA, levels(ex))[unclass(ex) + 1L], x)

---

Cut Numeric Vectors into Intervals

Description

interval divides x into intervals and, unlike cut, represents these as a numeric vector.

Usage

interval(x, ...)
## S3 method for class 'numeric'
interval(x, breaks = 50, ...)

Arguments

x	A numeric vector.
breaks	Either a numeric vector of two or more unique cut points or a single number (greater than or equal to 2) giving the number of intervals into which x is to be cut by cut.
...	Additional arguments, currently ignored.

Details

This is just a wrapper around cut where the resulting intervals are stored as numeric values for simplified computation.

Value

An object of class interval. A value of 0 encodes NA.

See Also

cut

Examples

(ix <- interval(x <- 0:100/100, breaks = 0:10/10))
(cx <- cut(x, breaks = 0:10/10))

attr(ix, "levels")
levels(ix)
levels(cx)

diag(table(ix, cx))

(ix <- interval(x <- c(NA, 0:100/100), breaks = 0:10/10))
ix[is.na(x)]
unclass(ix)[is.na(x)]

---

Coerse Variables in Data Frames to enum or interval

Description

Represents elements of a data frame as enum or interval.

Usage

inum(object, nmax = 20, ...)
## S3 method for class 'data.frame'
inum(object, nmax = 20, ignore = NULL, 
     total = FALSE, weights = NULL, as.interval = "",
     complete.cases.only = FALSE, meanlevels = FALSE, ...)

Arguments

object	A data frame.
nmax	Maximal number of categories for each of the numeric variables.
ignore	A character vector of variable names not to be discretised.
total	A logical. TRUE means that a condensed data frame of all variables is returned, FALSE a list of discretised variables.
weights	An optional vector of weights.
as.interval	A character vector of variable names to be converted to interval instead of enum.
complete.cases.only	A logical. TRUE removes all rows with missing values.
meanlevels	A logical. TRUE, the level is the mean of the observations in the corresponding bin. The default FALSE uses the largest observation in the bin.
...	Additional arguments, currently ignored.

Details

Each variable in object is converted to enum or interval.

Value

An object of class inum, basically a list of enum or interval objects. If total = TRUE, an integer vector with a data frame as levels attribute is returned. In this case, 0 means NA.

Examples

data("iris", package = "datasets")
iris[1,1] <- NA
inum(iris, nmax = 5)
inum(iris, nmax = 5, total = TRUE)
inum(iris, nmax = 5, total = TRUE, as.interval = "Sepal.Width",
     complete.cases.only = TRUE)

---