Return the first or last part of a dfm

For a dfm object, returns the first or last n documents and first nfeat features.

# S3 method for dfm
head(x, n = 6L, nf = nfeat(x), ...)

# S3 method for dfm
tail(x, n = 6L, nf = nfeat(x), ...)

Arguments

x	a dfm object
n	a single, positive integer. If positive, size for the resulting object: number of first/last documents for the dfm. If negative, all but the n last/first number of documents of x.
nf	the number of features to return, where the resulting object will contain the first ncol features; default is all features
...	additional arguments passed to other functions

Value

A dfm class object corresponding to the subset defined by n and nfeat.

Examples

head(data_dfm_lbgexample, 3, nf = 5)
#> Document-feature matrix of: 3 documents, 5 features (66.7% sparse).
#> 3 x 5 sparse Matrix of class "dfm"
#>     features
#> docs A B  C  D  E
#>   R1 2 3 10 22 45
#>   R2 0 0  0  0  0
#>   R3 0 0  0  0  0
head(data_dfm_lbgexample, -4)
#> Document-feature matrix of: 2 documents, 37 features (54.1% sparse).

tail(data_dfm_lbgexample)
#> Document-feature matrix of: 6 documents, 37 features (54.1% sparse).
tail(data_dfm_lbgexample, n = 3, nf = 4)
#> Document-feature matrix of: 3 documents, 4 features (66.7% sparse).
#> 3 x 4 sparse Matrix of class "dfm"
#>     features
#> docs ZH ZI ZJ ZK
#>   R4  0  0  0  0
#>   R5 22 10  3  2
#>   V1  0  0  0  0