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#       Rostam Abdollahi       #
#         R workshop           #
#     University of Tehran     #
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#          Introduction        #
#           WordCloud          #
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install.packages("tm")  # for text mining
install.packages("SnowballC") # for text stemming
install.packages("wordcloud") # word-cloud generator 
install.packages("RColorBrewer") # color palettes
# Load
#############################################
Step 1 : Install and load the required packages
library("tm")
library("SnowballC")
library("wordcloud")
library("RColorBrewer")
###############################
#Step 2: Create a text file

filePath <- "C:/Scientific/Scientific/WorkShops/7_WordCloud/RostamWeb_words.txt"
text <- readLines(filePath,encoding='UTF-8')


# Load the data as a corpus
docs <- Corpus(VectorSource(text))

#Inspect the content of the document
inspect(docs)
# Step3: Text transformation
toSpace <- content_transformer(function (x , pattern ) gsub(pattern, " ", x))

docs <- tm_map(docs, toSpace, "/")
docs <- tm_map(docs, toSpace, "@")
docs <- tm_map(docs, toSpace, "\\|")

###Cleaning the text

# Convert the text to lower case
docs <- tm_map(docs, content_transformer(tolower))
# Remove numbers
docs <- tm_map(docs, removeNumbers)
# Remove english common stopwords
docs <- tm_map(docs, removeWords, stopwords("english"))
# Remove your own stop word
# specify your stopwords as a character vector
docs <- tm_map(docs, removeWords, c("blabla1", "blabla2")) 
# Remove punctuations
docs <- tm_map(docs, removePunctuation)
# Eliminate extra white spaces
docs <- tm_map(docs, stripWhitespace)
# Text stemming
# docs <- tm_map(docs, stemDocument)

#Step 4 : Build a term-document matrix

dtm <- TermDocumentMatrix(docs)
m <- as.matrix(dtm)
v <- sort(rowSums(m),decreasing=TRUE)
d <- data.frame(word = names(v),freq=v)
head(d, 10)

#Step 5 : Generate the Word cloud
set.seed(1234)
wordcloud(words = d$word, freq = d$freq, min.freq = 1,
          max.words=200, random.order=FALSE, rot.per=0.35, 
          colors=brewer.pal(8, "Dark2"))

################################
#      We have finished        # 
#         Word Cloud           #
################################