Experiment 1

# BASIC R OPERATIONS
x <- c(1, 2, 3, 4, 5, 6)
sum(x)
mean(x)
median(x)
sqrt(x)
x^2
seq(1, 10)

# HISTOGRAM
x <- c(2,4,4,6,6,5,5,7,3,7,3,8,9,6,4,3,4,4,6,2,2,1,2,4,6,6,8)
hist(x, main = "Histogram", xlab = "Values", ylab = "Frequency")

# SCATTER PLOT
x <- c(1, 3, 5, 7, 9)
y <- c(2, 4, 6, 8, 10)
plot(x, y, main = "Scatter Plot", xlab = "X", ylab = "Y")

# TIME PLOT
plot(x, type = "b", main = "Time Plot", xlab = "Index", ylab = "X values")

# REGULAR EXPRESSIONS
grep("[a-zA-Z]", c(123, "abc"), value = TRUE)
grep("(ab){2}", c("aabb", "abaaabab", "abab"), value = TRUE)
grep("^(ab)", c("aabaa", "abaaabab", "bab"), value = TRUE)
grep("(ab)$", c("aabaa", "abaaabab", "bab"), value = TRUE)

# INSTALL PACKAGES (RUN ONCE)
install.packages(c("tm", "SnowballC", "wordcloud", "RColorBrewer"))

# LOAD LIBRARIES
library(tm)
library(SnowballC)
library(wordcloud)
library(RColorBrewer)

# READ TEXT FILE
text <- readLines(file.choose())

# CREATE CORPUS
docs <- Corpus(VectorSource(text))

# CLEAN TEXT
docs <- tm_map(docs, content_transformer(tolower))
docs <- tm_map(docs, removeNumbers)
docs <- tm_map(docs, removePunctuation)
docs <- tm_map(docs, stripWhitespace)

# TERM DOCUMENT MATRIX
dtm <- TermDocumentMatrix(docs)
m <- as.matrix(dtm)

# WORD FREQUENCY
v <- sort(rowSums(m), decreasing = TRUE)
d <- data.frame(word = names(v), freq = v)

# TOP WORDS
head(d, 10)

# WORD CLOUD
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"))