LDAvis with topicmodels package in R

topicmodels-ldavis.R

# install.packages("topicmodels")
# install.packages("reshape2")
# install.packages("LDAvis")
# install.packages("servr")

library(topicmodels)
library(reshape2)
library(LDAvis)
library(servr)

# create LDA model
tweets_lda <- topicmodels::LDA(dtm, k = 3, control = list(seed = 12))

post <- topicmodels::posterior(tweets_lda)
mat <- tweets_lda@wordassignments

# create input JSON for LDAvis
json <- LDAvis::createJSON(
    phi = post$terms, 
    theta = post$topics,
    vocab = colnames(post$terms),
    doc.length = slam::row_sums(mat, na.rm = TRUE),
    term.frequency = slam::col_sums(mat, na.rm = TRUE)
)
serVis(json)