program 15

Author

Gagana L

PROGRAM 15

step 1:- load ggplot2 for plotting

library(ggplot2)
library(dplyr)

Attaching package: 'dplyr'
The following objects are masked from 'package:stats':

    filter, lag
The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union
library(tidyr)
library(reshape2)

Attaching package: 'reshape2'
The following object is masked from 'package:tidyr':

    smiths

step 2:- load the data set

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 ...
str(ToothGrowth)
'data.frame':   60 obs. of  3 variables:
 $ len : num  4.2 11.5 7.3 5.8 6.4 10 11.2 11.2 5.2 7 ...
 $ supp: Factor w/ 2 levels "OJ","VC": 2 2 2 2 2 2 2 2 2 2 ...
 $ dose: num  0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 ...

step3:- Step 3 create hostogram using face wrap

ggplot(iris, aes(x = Sepal.Length)) +
  geom_histogram(binwidth = 0.3, color = "red", fill = "green", alpha = 0.7) +
  facet_wrap(~ Species) +
  labs(title = "Distribution of Sepal Length by Species",
       x = "Sepal Length",
       y = "Frequency") +
  theme_minimal()

step4:- define the function

df <- mtcars
df$cyl <- as.factor(df$cyl)  


ggplot(df, aes(x = mpg, fill = cyl)) +
  geom_density(alpha = 0.3) + 
  labs(title = "Density Plot of MPG by Number of Cylinders",
       x = "Miles per Gallon (MPG)",
       y = "Density") +
  scale_fill_brewer(palette = "Set1") +  
  theme_minimal()

step 5:- create a box plot with notches

ggplot(iris, aes(x = Species, y = Sepal.Length)) +
  geom_boxplot(
    notch = TRUE,
    notchwidth = 0.5,
    outlier.colour = "red",  # Correct spelling
    fill = "lightblue"
  ) +
  labs(
    title = "Basic Box Plot",
    x = "Species",
    y = "Sepal Length"
  ) +
  theme_minimal()

step 6:- Create violin plot: Sepal.Length by Species

ggplot(iris, aes(x = Species, y = Sepal.Length, fill = Species)) +
  geom_violin(trim = FALSE) +  # Show full distribution
  geom_boxplot(width = 0.1, fill = "white") +  # Optional: add boxplot inside violin
  labs(title = "Distribution of Sepal Length by Species",
       x = "Species",
       y = "Sepal Length") +
  theme_minimal()

step 7:- Convert dose to a factor

ToothGrowth$dose <- as.factor(ToothGrowth$dose)

step 8:- create the dot plot

ggplot(ToothGrowth, aes(x = dose, y = len, color = supp)) +
  geom_dotplot(
    binaxis = "y",
    stackdir = "center",
    dotsize = 0.6,
    position = position_dodge(0.8),
    binwidth = 1.5
  ) +
  labs(
    title = "Tooth Growth by Supplement Type and Dose",
    x = "Dose (mg)",
    y = "Tooth Length"
  ) +
  theme_minimal()

step 9:- preview the dataset

head(mtcars)
                   mpg cyl disp  hp drat    wt  qsec vs am gear carb
Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1
cor_matrix <- cor(mtcars)
cor_df <- as.data.frame(as.table(cor_matrix))
head(cor_df)
  Var1 Var2       Freq
1  mpg  mpg  1.0000000
2  cyl  mpg -0.8521620
3 disp  mpg -0.8475514
4   hp  mpg -0.7761684
5 drat  mpg  0.6811719
6   wt  mpg -0.8676594
# Use a sample dataset (replace mtcars with your own dataset if needed)
data <- mtcars

# Step 1: Calculate the correlation matrix
cor_matrix <- cor(data)

# Step 2: Convert the matrix to a long format data frame
cor_df <- melt(cor_matrix)
ggplot(cor_df, aes(x = Var1, y = Var2, fill = value)) +
  geom_tile(color = "white") +
  geom_text(aes(label = round(value, 2)), color = "black", size = 3.5) +
  
  scale_fill_gradient2(
    low = "green",
    high = "pink",
    mid = "white",
    midpoint = 0,
    limit = c(-1, 1),
    name = "Correlation"
  ) +
  theme_minimal() +
  coord_fixed() +
  labs(
    title = "Correlation Matrix Heatmap with Values",
    x = "",
    y = ""
  ) +
  theme(
    axis.text.x = element_text(angle = 45, vjust = 1, hjust = 1)
  )