Program_6

Author

Anusha Y K

Program 6:

Write an R script to construct a box plot showcasing the distribution of a continuous variable, grouped by a categorical variable, using ggplot2’s fill aesthetic.

###Step 1:Load Required Library

#Load ggplot2 package for visulization
#install.packages('ggplot2')
library(ggplot2)

###Step 2: Explore the inbuilt Dataset

#use the built-in íris' dataset.
#'Petal.Width' is a continuous variable.
#'species'is a categorical grouping variable.

str(iris) #View structure of the dataset.

'data.frame':   150 obs. of  5 variables:
 $ Sepal.Length: num  5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ...
 $ Sepal.Width : num  3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ...
 $ Petal.Length: num  1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...
 $ Petal.Width : num  0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...
 $ Species     : Factor w/ 3 levels "setosa","versicolor",..: 1 1 1 1 1 1 1 1 1 1 ...

head(iris) #View sample data

  Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1          5.1         3.5          1.4         0.2  setosa
2          4.9         3.0          1.4         0.2  setosa
3          4.7         3.2          1.3         0.2  setosa
4          4.6         3.1          1.5         0.2  setosa
5          5.0         3.6          1.4         0.2  setosa
6          5.4         3.9          1.7         0.4  setosa

###STEP 3: construct box plot

#Initialize ggplot with data and aesthetic mappings.

p <- ggplot(data = iris, aes(x = Species, y = Petal.Width, fill = Species))
p

#Add the box plot layer

p <- p+ geom_boxplot()
p

#Add title and axis labels and apply clean theme.
p<- p+ labs(
  title="Box plot",
  x="species",
  y="Petal Width")+
  theme_minimal()+
  theme(legend.position='top')
  p