技术问询：使用ggplot2绘制仿Excel Kutools风格的双变量对比柱状图

首先准备示例数据：

df <- data.frame(Unit = c("unit1", "unit2", "unit3"),
                 Aktual = c(1500, 2200, 3000),
                 Target = c(1600, 2100, 2900))

要实现和Kutools类似的对比效果，我们需要先把宽格式数据转换为ggplot2适配的长格式，再绘制并列柱状图，还可以添加数值标签和差值标注还原Kutools的细节：

步骤1：加载依赖包并转换数据格式 #

library(tidyverse)

# 将宽格式转为长格式，方便分组绘图
df_long <- df %>%
  pivot_longer(cols = -Unit, names_to = "Type", values_to = "Value")

步骤2：基础对比柱状图（还原Kutools核心布局） #

ggplot(df_long, aes(x = Unit, y = Value, fill = Type)) +
  # 设置并列柱子，调整间距让布局更紧凑
  geom_col(position = position_dodge(width = 0.8), width = 0.7) +
  # 使用类似Excel的配色区分实际值和目标值
  scale_fill_manual(values = c("Aktual" = "#1f77b4", "Target" = "#ff7f0e")) +
  # 设置图表标题和坐标轴标签
  labs(title = "实际值vs目标值对比", x = "单位", y = "数值", fill = "类型") +
  # 采用简洁的主题风格
  theme_minimal() +
  # 调整标题和图例位置
  theme(plot.title = element_text(hjust = 0.5, size = 14, face = "bold"),
        axis.title = element_text(size = 12),
        legend.position = "top")

步骤3：增强版（添加数值标签和差值标注） #

如果需要和Kutools一样显示柱子数值以及实际与目标的差值，可以额外计算差值并添加标注：

# 计算每个单位的差值并生成标注文本
df_diff <- df %>%
  mutate(Diff = Aktual - Target,
         Diff_Label = ifelse(Diff >= 0, paste("+", Diff), as.character(Diff)))

ggplot(df_long, aes(x = Unit, y = Value, fill = Type)) +
  geom_col(position = position_dodge(width = 0.8), width = 0.7) +
  # 在柱子顶部添加数值标签
  geom_text(aes(label = Value), position = position_dodge(width = 0.8), 
            vjust = -0.5, size = 4) +
  # 在每个单位上方添加差值标注
  geom_text(data = df_diff, aes(x = Unit, y = max(Value) * 1.1, label = Diff_Label),
            size = 4, color = "red", fontface = "bold") +
  scale_fill_manual(values = c("Aktual" = "#1f77b4", "Target" = "#ff7f0e")) +
  labs(title = "实际值vs目标值对比", x = "单位", y = "数值", fill = "类型") +
  # 调整y轴范围，留出标注空间
  ylim(0, max(df$Value) * 1.2) +
  theme_minimal() +
  theme(plot.title = element_text(hjust = 0.5, size = 14, face = "bold"),
        axis.title = element_text(size = 12),
        legend.position = "top")

这个实现完全匹配Kutools对比柱状图的效果：每个类别下并列显示两组数据，配色清晰，附带关键数值和差异标注，布局整洁直观。

内容的提问来源于stack exchange，提问作者Fadhil Dzikri