Word Frequency Dataframe

Returns a dataframe of words vs frequency

term_frequency(df, gram.min = 1, gram.max = 1)

Arguments

df	a dataframe with paper results
gram.min	minimum number of grams
gram.max	maximum number of grams

Examples

# NOT RUN {
my_url <- make_search_url(query = "neural network",
                          from_year = 1990,
                          to_year   = 1999,
                          how = "all")
df <- onepetro_page_to_dataframe(my_url)
term_frequency(df)
# }