R Notebook

Practical Tutorials

Create a dataframe

specie <- c(rep("Peach" , 3) , rep("Peanut" , 3) , rep("banana" , 3) , rep("triticum" , 3) )

condition <- rep(c("normal" , "stress" , "Nitrogen") , 4)
value <- abs(rnorm(12 , 0 , 15))
data <- data.frame(specie,condition,value)

data

ggplot(data, aes(fill=condition, y=value, x=specie)) + 
  geom_bar(position="dodge", stat="identity")

NA
NA

If and else if statement

Categorize value into three groups: High, Median and Low

# Using loop to categorize numerical values 

for (i in 1:nrow(data)){
  if (data$value[i]<5){
    data$Class[i]<-"Low"
  }else if (data$value[i]>=5 & data$value[i]<=10){
    data$Class[i]<-"Median"
  } else {
    data$Class[i]<-"High"
  }
}

head(data)