Get term frequencies and document frequencies from a document term matrix.

This function takes a document term matrix as input and returns a data frame with columns for term frequency, document frequency, and inverse-document frequency

TermDocFreq(dtm)

Arguments

dtm	A document term matrix of class dgCMatrix.

Value

Returns a data.frame with 4 columns. The first column, term is a vector of token labels. The second column, term_freq is the count of times term appears in the entire corpus. The third column doc_freq is the count of the number of documents in which term appears. The fourth column, idf is the log-weighted inverse document frequency of term.

Examples

# Load a pre-formatted dtm and topic model
data(nih_sample_dtm)
data(nih_sample_topic_model)

# Get the term frequencies 
term_freq_mat <- TermDocFreq(nih_sample_dtm)

str(term_freq_mat)
#> 'data.frame':	5210 obs. of  4 variables:
#>  $ term     : chr  "folding" "tosuprttedprtmnt" "importation" "hd" ...
#>  $ term_freq: num  1 1 1 1 1 1 1 1 1 1 ...
#>  $ doc_freq : int  1 1 1 1 1 1 1 1 1 1 ...
#>  $ idf      : num  4.61 4.61 4.61 4.61 4.61 ...