Coerce table to a frequency list

This function coerces an object of class table to an object of class freqlist.

Usage

as_freqlist(x, tot_n_tokens = NULL, sort_by_ranks = TRUE)

Arguments

x

Object of class table or named numeric vector that will be interpreted as such.

tot_n_tokens

Number representing the total number of tokens in the corpus from which the frequency list is derived. When tot_n_tokens is NULL, this total number of tokens will be taken to be the sum of the frequencies in x.

sort_by_ranks

Logical. If TRUE, the items in the frequency list are sorted by frequency rank. If FALSE, the items in the frequency list, depending on the input type, either are sorted alphabetically or are not sorted at all.

Value

An object of class freqlist, which is based on the class table. It has additional attributes and methods such as:

• base print(), as_data_frame(), summary() and sort,

• tibble::as_tibble(),

• an interactive explore() method,

• various getters, including tot_n_tokens(), n_types(), n_tokens(), values that are also returned by summary(), and more,

• subsetting methods such as keep_types(), keep_pos(), etc. including [] subsetting (see brackets).

Additional manipulation functions include type_freqs() to extract the frequencies of different items, freqlist_merge() to combine frequency lists, and freqlist_diff() to subtract a frequency list from another.

Objects of class freqlist can be saved to file with write_freqlist(); these files can be read with read_freqlist().

See also

freqlist()

Examples

toy_corpus <- "Once upon a time there was a tiny toy corpus.
It consisted of three sentences. And it lived happily ever after."

## make frequency list in a roundabout way
tokens <- tokenize(toy_corpus)
flist <- as_freqlist(table(tokens))
flist
#> Frequency list (types in list: 19, tokens in list: 21)
#> rank      type abs_freq nrm_freq
#> ---- --------- -------- --------
#>    1         a        2  952.381
#>    2        it        2  952.381
#>    3     after        1  476.190
#>    4       and        1  476.190
#>    5 consisted        1  476.190
#>    6    corpus        1  476.190
#>    7      ever        1  476.190
#>    8   happily        1  476.190
#>    9     lived        1  476.190
#>   10        of        1  476.190
#>   11      once        1  476.190
#>   12 sentences        1  476.190
#>   13     there        1  476.190
#>   14     three        1  476.190
#>   15      time        1  476.190
#>   16      tiny        1  476.190
#>   17       toy        1  476.190
#>   18      upon        1  476.190
#>   19       was        1  476.190

## more direct procedure
freqlist(toy_corpus, as_text = TRUE)
#> Frequency list (types in list: 19, tokens in list: 21)
#> rank      type abs_freq nrm_freq
#> ---- --------- -------- --------
#>    1         a        2  952.381
#>    2        it        2  952.381
#>    3     after        1  476.190
#>    4       and        1  476.190
#>    5 consisted        1  476.190
#>    6    corpus        1  476.190
#>    7      ever        1  476.190
#>    8   happily        1  476.190
#>    9     lived        1  476.190
#>   10        of        1  476.190
#>   11      once        1  476.190
#>   12 sentences        1  476.190
#>   13     there        1  476.190
#>   14     three        1  476.190
#>   15      time        1  476.190
#>   16      tiny        1  476.190
#>   17       toy        1  476.190
#>   18      upon        1  476.190
#>   19       was        1  476.190

## build frequency list from scratch: example 1
flist <- as_freqlist(c("a" = 12, "toy" = 53, "example" = 20))
flist
#> Frequency list (types in list: 3, tokens in list: 85)
#> rank    type abs_freq nrm_freq
#> ---- ------- -------- --------
#>    1     toy       53 6235.294
#>    2 example       20 2352.941
#>    3       a       12 1411.765

## build frequency list from scratch: example 2
flist <- as_freqlist(c("a" = 12, "toy" = 53, "example" = 20),
                     tot_n_tokens = 1300)
flist
#> Frequency list (types in list: 3, tokens in list: 85)
#> <total number of tokens: 1300>
#> rank    type abs_freq nrm_freq
#> ---- ------- -------- --------
#>    1     toy       53  407.692
#>    2 example       20  153.846
#>    3       a       12   92.308