Program 7

Develop a function in R to plot a function curve based on a mathematical equation provided as input, with different curve styles for each group, using ggplot2.

Step 1: Load the required library

library(ggplot2)

Step 2: Create data for the functions

# Create a sequence of x values ranging from -2pi to 2pi
x <- seq(-2*pi, 2*pi, length.out = 500)

# Evaluate sin(x) and cos(x) over the x range
y1 <- sin(x)
y2 <- cos(x)

# Combine data into one data frame
df <- data.frame(
  x = rep(x, 2),                        # Repeat x values for both functions
  y = c(y1, y2),                        # Combine y values: first sin(x, then cos(x))
  group = rep(c("sin(x)", "cos(x)"), each = length(x))  # Label each row by function
)

Step 3: Plot the Function Curves

Step 3.1: Initialize the ggplot Object

# Start building the ggplot using the data frame and aesthetics

p <- ggplot(df, aes(x = x, y = y, color = group, linetype = group))

Step 3.2: Add the Line Geometry

# Add smooth lines to represent each function curve

p <- p + geom_line(size = 1.2)

Warning: Using `size` aesthetic for lines was deprecated in ggplot2 3.4.0.
ℹ Please use `linewidth` instead.

Step 3.3: Add Plot Labels

# Add title, axis labels, and legends

P <- p + labs(title = "Function Curves: sin(x) and cos(x)",
              x = "x",
              y = "y = f(x)",
              color = "function",
              linetype = "Function")

Step 3.4: Apply a Clean Theme

# Use a clean and simple background theme

p <- p + theme_minimal()
p