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Create a categorical distance matrix

Source: R/dist_category.R
dist_category.Rd

dist_category() takes a factor vector and returns a pairwise distance matrix indicating whether observations belong to different categories.

Usage

dist_category(x)

Arguments

x

A factor vector.

Value

A numeric matrix with one row and one column for each element of x. If x has names, they are used as row and column names.

Details

The returned matrix contains:

  • 0 when two observations are in the same category

  • 1 when two observations are in different categories

  • NA when either observation has a missing value

See also

same_category()

Examples

group <- factor(c("A", "A", "B", "C"))

dist_category(group)
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    1    1
#> [2,]    0    0    1    1
#> [3,]    1    1    0    1
#> [4,]    1    1    1    0

# Named input preserves names in the output matrix
named_group <- factor(c("red", "blue", "red"))
names(named_group) <- c("sample1", "sample2", "sample3")

dist_category(named_group)
#>         sample1 sample2 sample3
#> sample1       0       1       0
#> sample2       1       0       1
#> sample3       0       1       0

# Missing values return NA for comparisons involving the missing value
group_with_na <- factor(c("A", NA, "B"))
dist_category(group_with_na)
#>      [,1] [,2] [,3]
#> [1,]    0   NA    1
#> [2,]   NA   NA   NA
#> [3,]    1   NA    0