cjk_char_counts() returns one row per distinct CJK character in a text
column, with the script and Unicode block it belongs to and how often it
occurred. It is the frequency table you would otherwise write by hand before
every CJK analysis.
Arguments
- data
A data frame or tibble containing a text column.
- col
The text column to scan, supplied unquoted. A non-character column is coerced with
as.character(); seehas_cjk()for why that makes a numeric column a poor thing to measure. A list-column is an error rather than a coercion, for the reason given there.
Value
A tibble with one row per distinct character and columns char,
codepoint (integer), script, block and n. A column with no CJK in
it gives a zero-row tibble with those columns.
Details
Only CJK characters appear; Latin letters, digits and whitespace are
dropped. "CJK" means any block listed by cjk_blocks(), so ideographic
punctuation and fullwidth forms are included and are labelled as such in
script – which makes this the quickest way to find out that a column you
thought was clean is full of fullwidth spaces.
Rows are ordered by descending count, and ties are broken by first appearance in the column rather than by the session's collation, so the output does not change with the locale.
Grouping is ignored: the counts are always for the whole column. Use
dplyr::group_modify() if you need them per group.
See also
cjk_summary() for the column-level figures, cjk_blocks() for
the block table these labels come from.
Examples
# "Chinese writing" twice over, then "the Japanese language" in kanji and
# kana, then a row with no CJK at all
df <- data.frame(
text = c("\u4e2d\u6587\u4e2d\u6587",
"\u65e5\u672c\u306e\u3053\u3068\u3070",
"ascii only")
)
cjk_char_counts(df, text)
#> # A tibble: 8 × 5
#> char codepoint script block n
#> <chr> <int> <chr> <chr> <int>
#> 1 中 20013 han CJK Unified Ideographs 2
#> 2 文 25991 han CJK Unified Ideographs 2
#> 3 日 26085 han CJK Unified Ideographs 1
#> 4 本 26412 han CJK Unified Ideographs 1
#> 5 の 12398 hiragana Hiragana 1
#> 6 こ 12371 hiragana Hiragana 1
#> 7 と 12392 hiragana Hiragana 1
#> 8 ば 12400 hiragana Hiragana 1