R语言循环实现序列匹配：筛选相似度≥0.8的描述

Hey there! No need to apologize for asking basic questions—we all start somewhere 😊 Let's tackle your problem step by step.

First, let's clarify what we need to do: calculate the similarity between your new description (new_cr) and every description in your dataframe, then pull out all entries where the similarity score is ≥0.8 (adjust if your score range is 0-100 instead of 0-1) as a list.

Method 1: Base R (no explicit loops) #

We can use sapply to iterate over each description in your dataframe, compute the similarity score, then filter based on your threshold:

library(fuzzywuzzyR)

# Example value for new_cr (replace with your actual input)
new_cr <- "grant system admin rights"

# Calculate similarity scores for all descriptions
similarity_scores <- sapply(df$description, function(desc) {
  matcher <- SequenceMatcher$new(string1 = desc, string2 = new_cr)
  matcher$ratio()
})

# Extract descriptions with score ≥0.8 and convert to a list
similar_descriptions <- as.list(df$description[similarity_scores >= 0.8])

Method 2: Using purrr (cleaner & efficient for larger datasets) #

If you're open to using the purrr package (part of the tidyverse), it provides a more readable way to handle iteration, which is especially useful if your dataframe is large:

library(fuzzywuzzyR)
library(purrr)

new_cr <- "grant system admin rights"

# Compute similarity scores with map_dbl (returns a numeric vector)
similarity_scores <- map_dbl(df$description, ~{
  SequenceMatcher$new(string1 = .x, string2 = new_cr)$ratio()
})

# Filter and convert to list
similar_descriptions <- df$description[similarity_scores >= 0.8] %>% as.list()

Important Note: #

Double-check the range of the ratio() output! If SequenceMatcher$ratio() returns values between 0-100 (percentages) instead of 0-1, you'll need to adjust your threshold to 80 instead of 0.8.

Both methods avoid manual for loops and are optimized for R's vectorized operations, making them more efficient than writing a loop yourself.

内容的提问来源于stack exchange，提问作者user2906657