TidyText マイニング セクション 3.3に素敵なコードの塊があり、それを自分のデータセットに複製しようとしています。ただし、私のデータでは、ggplot に降順でデータが必要であること、および特定のtop_n.
TidyText Mining からコードを実行すると、本に示されているのと同じチャートが得られます。ただし、これを自分のデータセットで実行すると、ファセット ラップに top_n が表示されず (ランダムな数のカテゴリが表示されるようです)、各ファセット内のデータが降順で並べ替えられません。
いくつかのランダムなテキスト データと完全なコードを使用してこの問題を再現できますが、問題を再現することもできますが、mtcarsこれには本当に混乱します。
次のグラフでは、ファセットごとに mpg が降順で表示され、各ファセットで上位1 つのカテゴリのみが表示されることを期待しています。それは私にとってもそうではありません。
require(tidyverse)
mtcars %>%
arrange (desc(mpg)) %>%
mutate (gear = factor(gear, levels = rev(unique(gear)))) %>%
group_by(am) %>%
top_n(1) %>%
ungroup %>%
ggplot (aes (gear, mpg, fill = am)) +
geom_col (show.legend = FALSE) +
labs (x = NULL, y = "mpg") +
facet_wrap(~am, ncol = 2, scales = "free") +
coord_flip()
しかし、私が本当に欲しいのは、このようなチャートを TidyText ブックのようにソートすることです (データは例のみ)。
require(tidyverse)
require(tidytext)
starwars <- tibble (film = c("ANH", "ESB", "ROJ"),
text = c("It is a period of civil war. Rebel spaceships, striking from a hidden base, have won their first victory against the evil Galactic Empire. During the battle, Rebel spies managed to steal secret plans to the Empire's ultimate weapon, the DEATH STAR, an armored space station with enough power to destroy an entire planet. Pursued by the Empire's sinister agents, Princess Leia races home aboard her starship, custodian of the stolen plans that can save her people and restore freedom to the galaxy.....",
"It is a dark time for the Rebellion. Although the Death Star has been destroyed, Imperial troops have driven the Rebel forces from their hidden base and pursued them across the galaxy. Evading the dreaded Imperial Starfleet, a group of freedom fighters led by Luke Skywalker has established a new secret base on the remote ice world of Hoth. The evil lord Darth Vader, obsessed with finding young Skywalker, has dispatched thousands of remote probes into the far reaches of space....",
"Luke Skywalker has returned to his home planet of Tatooine in an attempt to rescue his friend Han Solo from the clutches of the vile gangster Jabba the Hutt. Little does Luke know that the GALACTIC EMPIRE has secretly begun construction on a new armored space station even more powerful than the first dreaded Death Star. When completed, this ultimate weapon will spell certain doom for the small band of rebels struggling to restore freedom to the galaxy...")) %>%
unnest_tokens(word, text) %>%
mutate(film = as.factor(film)) %>%
count(film, word, sort = TRUE) %>%
ungroup()
total_wars <- starwars %>%
group_by(film) %>%
summarize(total = sum(n))
starwars <- left_join(starwars, total_wars)
starwars <- starwars %>%
bind_tf_idf(word, film, n)
starwars %>%
arrange(desc(tf_idf)) %>%
mutate(word = factor(word, levels = rev(unique(word)))) %>%
group_by(film) %>%
top_n(10) %>%
ungroup %>%
ggplot(aes(word, tf_idf, fill = film)) +
geom_col(show.legend = FALSE) +
labs (x = NULL, y = "tf-idf") +
facet_wrap(~film, ncol = 2, scales = "free") +
coord_flip()