使用R表示3个变量的堆叠条形图

install.packages("ggplot2")
library(ggplot2)

data <- data.frame(
  Category = c("Category 1", "Category 2", "Category 3"),
  A = c(10, 15, 20),
  B = c(5, 8, 12),
  C = c(3, 6, 9)
)

ggplot(data, aes(x = Category, y = A, fill = "A")) +
  geom_bar(stat = "identity") +
  geom_bar(aes(y = B, fill = "B"), stat = "identity") +
  geom_bar(aes(y = C, fill = "C"), stat = "identity")

ggplot(data, aes(x = Category, y = A, fill = "A")) +
  geom_bar(stat = "identity") +
  geom_bar(aes(y = B, fill = "B"), stat = "identity") +
  geom_bar(aes(y = C, fill = "C"), stat = "identity") +
  labs(title = "Stacked Bar Chart of 3 Variables",
       x = "Category",
       y = "Value") +
  scale_fill_manual(values = c("A" = "red", "B" = "blue", "C" = "green")) +
  theme(legend.title = element_blank())