program 11

Author

Vaishnavi

Objective

To generate a basic box plot using ggplot2, enchanced with

Step 1: Load Required Package

We use ggplot2 package for data visualization.If It’s not aleready installed,you can it using:

#install.Packages("ggplot")
library(ggplot2)

Step 2: Use Inbuilt Datset

we will - setosa - versicolor - virginica

#Load and preview the datset
data(iris)
head(iris)
  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
str(iris)
'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 ...

The Species column is catgericoal ## Step 3: Create a Notched Box Plot Grouped by Species

we now create a box for Sepal.Length,Grouped by Species.we’ll enchance the plot using:- Notches to show the confidence interval around the median Outliner highliting using color and shape -Aesthetic enhancement like full color and theme

p <- ggplot(iris,aes(x = Species,y = Sepal.Length))
p

p <- ggplot(iris,aes(x = Species,y = Sepal.Length)) +
  geom_boxplot(
    notch =TRUE,
    notchwidth = 0.6,
    outlier.color = "red",
    outlier.shape = 16,
    fill = "skyblue",
    alpha = 0.7
)
p

p <- ggplot(iris,aes(x = Species,y = Petal.Length)) +
  geom_boxplot(
    notch =TRUE,
    notchwidth = 0.6,
    outlier.color = "red",
    outlier.shape = 16,
    fill = "skyblue",
    alpha = 0.7
)
p

p <- p + 
  labs(
    title = "Sepal length distribution by iris species",
    subtitle = "Box plot with notices and outlier highlighting",
    x = "Species",
    y = "Sepal.Length"
    ) +
  theme_minimal()
p

p <- ggplot(iris,aes(x = Species,y = Petal.Width)) +
  geom_boxplot(
    notch =TRUE,
    notchwidth = 0.6,
    outlier.color = "red",
    outlier.shape = 16,
    fill = "skyblue",
    alpha = 0.7
)
p
Notch went outside hinges
ℹ Do you want `notch = FALSE`?

  • Box Plot: Each box summarizes the distribution of Sepal.Length for a species - showing the interquartile range (IQR) median,and potential outliers.

  • Notches:

_ Outliers:Point that fall outside 1.5