使用过滤器在R中制作条形图

# 加载ggplot2库
library(ggplot2)

# 准备数据集并应用过滤器
data <- data.frame(category = c("A", "B", "C", "A", "B", "C"),
                   value = c(10, 15, 8, 12, 9, 11))

filtered_data <- data %>%
  filter(category == "A") # 过滤出category为"A"的数据

# 创建条形图
bar_plot <- ggplot(filtered_data, aes(x = category, y = value)) +
  geom_bar(stat = "identity")

# 自定义条形图外观
bar_plot <- bar_plot +
  labs(title = "Bar Plot Example", x = "Category", y = "Value") +
  theme(plot.title = element_text(size = 14, face = "bold"),
        axis.title = element_text(size = 12))

# 显示条形图
print(bar_plot)