Drop Unused Logical Map Values

Remove any unused values from a logical map

# S3 method for LogMap
droplevels(x, ...)

Arguments

x

A LogMap object

...

Ignored

Value

x with values not present in any observation removed

See also

Logical map objects, validity, and interaction methods: LogMap, LogMap-validity, as.matrix.LogMap(), intersect.LogMap(), labels.LogMap()

Examples

map <- LogMap(letters[1:10])
map[['obs']] <- c(1, 3, 7)
map[['entry']] <- c(2, 7, 10)

# Remove unused values
map <- droplevels(map)
map
#> A logical map for 5 values across 2 observations
map[[]]
#>     obs entry
#> a  TRUE FALSE
#> b FALSE  TRUE
#> c  TRUE FALSE
#> g  TRUE  TRUE
#> j FALSE  TRUE