Program 15

Summary of all programs in part B

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

data(mtcars)
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

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

data(iris)

data(ToothGrowth) 
head(ToothGrowth)

   len supp dose
1  4.2   VC  0.5
2 11.5   VC  0.5
3  7.3   VC  0.5
4  5.8   VC  0.5
5  6.4   VC  0.5
6 10.0   VC  0.5

ggplot(iris, aes(x = Sepal.Length)) +    geom_histogram(binwidth = 0.3, fill = "skyblue",color = "black") +    facet_wrap(~ Species) +   
  labs(title = "Distribution of sepal length by Species",        x = "Sepal Length (cm)",       
y = "Frequency") +    

theme_minimal()

plot_density_by_group <- function(data, numeric_var, group_var, fill = TRUE) {   
  ggplot(data, aes_string(x = numeric_var, color = group_var, fill = group_var)) +     
    geom_density(alpha = if (fill) 0.4 else 0) +     labs(       title = paste("Density Plot of", numeric_var, "by", group_var),       x = numeric_var,       
    y = "Density"     ) +     
    theme_minimal() } 
plot_density_by_group(iris, "Sepal.Length", "Species")

Warning: `aes_string()` was deprecated in ggplot2 3.0.0.
ℹ Please use tidy evaluation idioms with `aes()`.
ℹ See also `vignette("ggplot2-in-packages")` for more information.

ggplot(iris, aes(x = Species, y = Sepal.Length)) +   
  geom_boxplot(     notch = TRUE,     
                    notchwidth = 0.6,     
                    staplewidth = 0.4,     
                    fill = "red",     
                    
color = "skyblue"   ) +   
  labs(     title = "Box Plot for Iris",     
            x = "Species",     
            y = "Sepal Length"   ) +   
  theme_minimal() 

ggplot(iris, aes(x = Species , y = Sepal.Length , 
                 fill = Species))+   
  geom_violin(trim = FALSE, 
              alpha=0.6, 
              color= "black")+     
  labs(title = "Distributions of petal length by iris Species",        x = "Species",        
      y = "Petal.Length")+   
  theme_minimal(base_size = 14)

data(mtcars)

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

# Convert dose to a factor for grouping 
ToothGrowth$dose <- as.factor(ToothGrowth$dose)  # Plot with defined binwidth 
ggplot(ToothGrowth, aes(x = dose, y = len, color = supp)) +   geom_dotplot(     binaxis = 'y',     stackdir = 'center',     position = position_dodge(width = 0.8),     dotsize = 0.6,     binwidth = 1.5  # Controls spacing of dots on y-axis   
                                                                                ) +   labs(     title = "Dot Plot of Tooth Length by Dose and Supplement Type",     x = "Dose (mg/day)",     y = "Tooth Length",     color = "Supplement Type"   ) +   theme_minimal()

ggplot(cor_df, aes(x = Var1, y = Var2, fill = Freq)) +
  geom_tile(color = "white") +  # Draw tile borders
  scale_fill_gradient2(
    low = "blue", mid = "white", high = "red", 
    midpoint = 0, limit = c(-1, 1),
    name = "Correlation"
  ) +
  geom_text(aes(label = round(Freq, 2)), size = 3) +  # Show values
  theme_minimal() +
  labs(
    title = "Correlation Matrix (mtcars)",
    x = "", y = ""
  ) +
  theme(axis.text.x = element_text(angle = 45, hjust = 1))