LatentSemanticAnalysis {text2vec} | R Documentation |
Latent Semantic Analysis model
Description
Creates LSA(Latent semantic analysis) model. See https://en.wikipedia.org/wiki/Latent_semantic_analysis for details.
Usage
LatentSemanticAnalysis
LSA
Format
R6Class
object.
Usage
For usage details see Methods, Arguments and Examples sections.
lsa = LatentSemanticAnalysis$new(n_topics) lsa$fit_transform(x, ...) lsa$transform(x, ...) lsa$components
Methods
$new(n_topics)
create LSA model with
n_topics
latent topics$fit_transform(x, ...)
fit model to an input sparse matrix (preferably in
dgCMatrix
format) and then transformx
to latent space$transform(x, ...)
transform new data
x
to latent space
Arguments
- lsa
A
LSA
object.- x
An input document-term matrix. Preferably in
dgCMatrix
format- n_topics
integer
desired number of latent topics.- ...
Arguments to internal functions. Notably useful for
fit_transform()
- these arguments will be passed torsparse::soft_svd
Examples
data("movie_review")
N = 100
tokens = word_tokenizer(tolower(movie_review$review[1:N]))
dtm = create_dtm(itoken(tokens), hash_vectorizer(2**10))
n_topics = 5
lsa_1 = LatentSemanticAnalysis$new(n_topics)
d1 = lsa_1$fit_transform(dtm)
# the same, but wrapped with S3 methods
d2 = fit_transform(dtm, lsa_1)
[Package text2vec version 0.6.4 Index]