gdata (version 3.0.1)

nPairs: Number of variable pairs

Description

Count the number of pairs between variables.

Usage

nPairs(x, margin=FALSE, names=TRUE, abbrev=TRUE, ...)

Value

Matrix of order \(k\), where \(k\) is the number of columns in x. Values in a matrix represent the number of pairs between columns/variables in

x. If margin=TRUE, the number of columns is \(k+1\) and the last column represents the cumulative number of pairing all variables.

Arguments

x

data.frame or a matrix

margin

logical, calculate the cumulative number of “pairs”

names

logical, add row/col-names to the output

abbrev

logical, abbreviate names

...

other arguments passed to abbreviate

Author

Gregor Gorjanc

Details

The class of returned matrix is nPairs and matrix. There is a summary method, which shows the opposite information - counts how many times each variable is known, while the other variable of a pair is not. See examples.

See Also

abbreviate

Examples

# Test data
test <- data.frame(V1=c(1, 2, 3, 4, 5),
                   V2=c(NA, 2, 3, 4, 5),
                   V3=c(1, NA, NA, NA, NA),
                   V4=c(1, 2, 3, NA, NA))

# Number of variable pairs
nPairs(x=test)

# Without names
nPairs(x=test, names=FALSE)

# Longer names
colnames(test) <- c("Variable1", "Variable2", "Variable3", "Variable4")
nPairs(x=test)

# Margin
nPairs(x=test, margin=TRUE)

# Summary
summary(object=nPairs(x=test))