计算R中两个单词的余弦相似度？

Question

I have a text file and would like to create semantic vectors for each word in the file. I would then like to extract the cosine similarity for about 500 pairs of words. What is the best package in R for doing this?

Answer 1

You can use lsa library. cosine function of the library gives a matrix of cosine similarity. It takes a matrix as input.

Answer 2

If I understand your problem correctly, you want the cosine similarity of two vectors of words. Let us start with the cosine similiarity of two words only:

library(stringdist)
d <- stringdist("ca","abc",method="cosine")

The result is d= 0.1835034 as expected.

There is also a function stringdistmatrix() contained in that package which calculates the distance between all pairs of strings:

> d <- stringdistmatrix(c('foo','bar','boo','baz'))
> d
  1 2 3
2 3    
3 1 2  
4 3 1 2

For your purpose, you can simply use something like this

stringdist(c("ca","abc"),c("aa","abc"),method="cosine")

The result are the measure for the distances between ca and aa on the one hand and abc compared with abc on the other hand:

0.2928932 0.0000000

Disclaimer: The library stringdist is brand new (June 2019), but seems to work nicely. I am not associated with the authors of the library.