在R中组合多个数据集

# 创建两个示例数据框
df1 <- data.frame(id = c(1, 2, 3), name = c("Alice", "Bob", "Charlie"))
df2 <- data.frame(id = c(2, 3, 4), age = c(25, 30, 35))

# 内部连接
merged_inner <- merge(df1, df2, by = "id")
print(merged_inner)

# 左连接
merged_left <- merge(df1, df2, by = "id", all.x = TRUE)
print(merged_left)

# 右连接
merged_right <- merge(df1, df2, by = "id", all.y = TRUE)
print(merged_right)

# 外部连接
merged_outer <- merge(df1, df2, by = "id", all = TRUE)
print(merged_outer)

# 创建两个具有相同列的数据框
df3 <- data.frame(id = c(1, 2), value = c(10, 20))
df4 <- data.frame(id = c(3, 4), value = c(30, 40))

# 堆叠数据框
stacked_df <- rbind(df3, df4)
print(stacked_df)

merged_df <- merge(df1, df2, by.x = "ID", by.y = "id", check.names = FALSE)

df1_unique <- unique(df1)
df2_unique <- unique(df2)
merged_unique <- merge(df1_unique, df2_unique, by = "id")