R: stopwords
Revision as of 12:58, 1 November 2018 by Onnowpurbo (talk | contribs)
install.packages("stopwords")
# atau
install.packages("devtools")
devtools::install_github("quanteda/stopwords")
head(stopwords::stopwords("de", source = "snowball"), 20)
head(stopwords::stopwords("id", source = "stopwords-iso"), 20)
stopwords::stopwords_getsources()
stopwords::stopwords_getlanguages("snowball")
stopwords::stopwords_getlanguages("stopwords-iso")
Contoh 1
documents = c("She had toast for breakfast",
"The coffee this morning was excellent",
"For lunch let's all have pancakes",
"Later in the day, there will be more talks",
"The talks on the first day were great",
"The second day should have good presentations too")
library(tm)
documents <- Corpus(VectorSource(documents))
documents = tm_map(documents, content_transformer(tolower))
documents = tm_map(documents, removePunctuation)
documents = tm_map(documents, removeWords, stopwords("english"))
documents
Contoh 2
#downloading and installing the package from CRAN
install.packages("tm")
#loading tm
library(tm)
#loading a text file from local computer newdata<- readlines(filepath) #Load data as corpus #VectorSource() creates character vectors mydata <- Corpus(VectorSource(newdata))
# convert to lower case
mydata <- tm_map(mydata, content_transformer(tolower))
#remove ������ what would be emojis
mydata<-tm_map(mydata, content_transformer(gsub), pattern="\\W",replace=" ")
# remove URLs
removeURL <- function(x) gsub("http[^[:space:]]*", "", x)
mydata <- tm_map(mydata, content_transformer(removeURL))
# remove anything other than English letters or space
removeNumPunct <- function(x) gsub("[^[:alpha:][:space:]]*", "", x)
mydata <- tm_map(mydata, content_transformer(removeNumPunct))
# remove stopwords
mydata <- tm_map(mydata, removeWords, stopwords("english"))
#u can create custom stop words using the code below.
#myStopwords <- c(setdiff(stopwords('english'), c("r", "big")),"use", "see", "used", "via", "amp")
#mydata <- tm_map(mydata, removeWords, myStopwords)
# remove extra whitespace
mydata <- tm_map(mydata, stripWhitespace)
# Remove numbers
mydata <- tm_map(mydata, removeNumbers)
# Remove punctuations
mydata <- tm_map(mydata, removePunctuation)
# stemmimg library(SnowballC) mydata <- tm_map(mydata, stemDocument)