| Extract.factor {base} | R Documentation |
Extract or Replace Parts of a Factor
Description
Extract or replace subsets of factors.
Usage
## S3 method for class 'factor'x[..., drop = FALSE]## S3 method for class 'factor'x[[...]]## S3 replacement method for class 'factor'x[...] <- value## S3 replacement method for class 'factor'x[[...]] <- valueArguments
x | a factor. |
... | a specification of indices – see |
drop | logical. If true, unused levels are dropped. |
value | character: a set of levels. Factor values are coerced tocharacter. |
Details
When unused levels are dropped the ordering of the remaining levels ispreserved.
Ifvalue is not inlevels(x), a missing value isassigned with a warning.
Anycontrasts assigned to the factor are preservedunlessdrop = TRUE.
The[[ method supports argumentexact.
Value
A factor with the same set of levels asx unlessdrop = TRUE.
See Also
Examples
## following example(factor)(ff <- factor(substring("statistics", 1:10, 1:10), levels = letters))ff[, drop = TRUE]factor(letters[7:10])[2:3, drop = TRUE][Packagebase version 4.6.0Index]