如何统计.csv文件中包含文本和日期值的列表中特定正/负单词的出现频率？在R中

data <- read.csv("filename.csv")

text_column <- data$column_name

text_column <- tolower(text_column)
text_column <- gsub("[[:punct:]]", "", text_column)
text_column <- gsub("[[:digit:]]", "", text_column)

words <- strsplit(text_column, "\\s+")
words <- unlist(words)

stopwords <- c("a", "an", "the", ...)
words <- words[!words %in% stopwords]

word_freq <- table(words)

positive_words <- c("good", "excellent", ...)
negative_words <- c("bad", "poor", ...)
positive_freq <- word_freq[names(word_freq) %in% positive_words]
negative_freq <- word_freq[names(word_freq) %in% negative_words]

positive_freq <- sort(positive_freq, decreasing = TRUE)
negative_freq <- sort(negative_freq, decreasing = TRUE)