加载gcookbook包，探索cabbage_exp维度和结构

1. 加载gcookbook包，探索cabbage_exp维度和结构
2. 以Date为横坐标，Weight为纵坐标，Cultivar为分组变量，作簇状柱状图
3. 在第二题的基础上，以“Pastel2”为填充色，作柱状图
4. 在第三题的基础上，柱状图上标注Weight具体数字
5. 在第二题的基础上，作堆叠柱状图，Y轴无需统一为100%
6. 在第二题的基础上，纵坐标统一为100%，作堆叠柱状图

# 1
library(gcookbook)
dim(cabbage_exp)  
str(cabbage_exp)  

# 2
library(ggplot2)

ggplot(cabbage_exp, aes(x = Date, y = Weight, fill = Cultivar)) +
  geom_bar(stat = "identity", position = "dodge") +
  labs(title = "簇状柱状图", x = "日期", y = "重量") +
  theme_minimal() +
  theme(
    plot.title = element_text(hjust = 0.5, size = 15)  
  )

# 3
ggplot(cabbage_exp, aes(x = Date, y = Weight, fill = Cultivar)) +
  geom_bar(stat = "identity", position = "dodge") +
  scale_fill_brewer(palette = "Pastel2") +
  labs(title = "簇状柱状图", x = "日期", y = "重量") +
  theme_minimal() +
  theme(
    plot.title = element_text(hjust = 0.5, size = 15)  
  )

# 4
ggplot(cabbage_exp, aes(x = Date, y = Weight, fill = Cultivar)) +
  geom_bar(stat = "identity", position = "dodge") +
  scale_fill_brewer(palette = "Pastel2") +
  geom_text(aes(label = Weight), position = position_dodge(width = 0.9), vjust = -0.5) +
  labs(title = "柱状图", x = "日期", y = "重量") +
  theme_minimal() +
  theme(
    plot.title = element_text(hjust = 0.5, size = 15)  
  )

# 5
ggplot(cabbage_exp, aes(x = Date, y = Weight, fill = Cultivar)) +
  geom_bar(stat = "identity", position = "stack") +
  labs(title = "堆叠柱状图", x = "日期", y = "重量") +
  theme_minimal() +
  theme(
    plot.title = element_text(hjust = 0.5, size = 15) 
  )

# 6
ggplot(cabbage_exp, aes(x = Date, y = Weight, fill = Cultivar)) +
  geom_bar(stat = "identity", position = "fill") +
  scale_y_continuous(labels = scales::percent) +
  labs(title = "堆叠柱状图", x = "日期", y = "比例") +
  theme_minimal() +
  theme(
    plot.title = element_text(hjust = 0.5, size = 15) 
  )