R: Convenience wrappers for dfm convert

convert-wrappers {quanteda} | R Documentation

## Convenience wrappers for dfm convert

### Description

To make the usage as consistent as possible with other packages, quanteda also provides shortcut wrappers to `convert()`, designed to be similar in syntax to analogous commands in the packages to whose format they are converting.

### Usage

    dfm2austin(x)

    dfm2tm(x, weighting = tm::weightTf)

    dfm2lda(x, omit_empty = TRUE)

    dtm2lda(x, omit_empty = TRUE)

    dfm2dtm(x, omit_empty = TRUE)

    dfm2stm(x, docvars = NULL, omit_empty = TRUE)

### Arguments

`x` | the dfm to be converted
`weighting` | a tm weight, see `tm::weightTf()`
`omit_empty` | logical; if `TRUE`, omit empty documents and features from the converted dfm. This is required for some formats (such as STM) that do not accept empty documents. Only used when `to = "lda"` or `to = "topicmodels"`. For `to = "stm"` format, `omit_empty`` is always` TRUE'.
`docvars` | optional data.frame of document variables used as the `meta` information in conversion to the stm package format. This aids in selecting the document variables only corresponding to the documents with non-zero counts. Only affects the "stm" format.
`...` | additional arguments used only by `as.DocumentTermMatrix`

### Details

`dfm2lda` provides converts a dfm into the list representation of terms in documents used by the lda package (a list with components "documents" and "vocab" as needed by `lda::lda.collapsed.gibbs.sampler()`).

`dfm2ldaformat` provides converts a dfm into the list representation of terms in documents used by the lda package (a list with components "documents" and "vocab" as needed by `lda::lda.collapsed.gibbs.sampler()`).

### Value

A converted object determined by the value of `to` (see above). See conversion target package documentation for more detailed descriptions of the return formats.

### Note

Additional coercion methods to base R objects are also available:

`[as.data.frame](x)`

  converts a dfm into a data.frame

`[as.matrix](x)`

  converts a dfm into a matrix

### Examples

    dfmat <- corpus_subset(data_corpus_inaugural, Year > 1970) %>%
        tokens() %>%
        dfm()

    ## Not run:
    # shortcut conversion to lda package list format
    identical(quanteda:::dfm2lda(dfmat), convert(dfmat, to = "lda"))

    ## End(Not run)

    ## Not run:
    # shortcut conversion to lda package list format
    identical(dfm2ldaformat(dfmat), convert(dfmat, to = "lda"))

    ## End(Not run)

[Package quanteda version 3.0.0 Index]