ggplot：错误：美学必须是长度1或与数据相同（10）：x，y，组答案

【问题标题】：ggplot: Error: Aesthetics must be either length 1 or the same as the data (10): x, y, groupggplot：错误：美学必须是长度1或与数据相同（10）：x，y，组
【发布时间】：2017-06-07 04:12:27
【问题描述】：

我有一个小数据集，我想用折线图绘制它：

 > Gain
     quantile Positives Total_Examples Positive_Prevalence     Lift Cumsum_Positives
 1:     (0, ]         1              1                   1 1.428571        0.1428571
 2: (1.9,2.8]         1              1                   1 1.428571        0.2857143
 3: (2.8,3.7]         1              1                   1 1.428571        0.4285714
 4: (3.7,4.6]         1              1                   1 1.428571        0.5714286
 5: (4.6,5.5]         1              1                   1 1.428571        0.7142857
 6: (5.5,6.4]         1              1                   1 1.428571        0.8571429
 7: (6.4,7.3]         1              1                   1 1.428571        1.0000000
 8: (7.3,8.2]         0              1                   0 0.000000        1.0000000
 9: (8.2,9.1]         0              1                   0 0.000000        1.0000000
10:  (9.1,10]         0              1                   0 0.000000        1.0000000

我的代码如下：

    ggplot(Gain ) +
  geom_area(aes(x = quantile, y = Cumsum_Positives, group = 1), color = "red", fill = "red", alpha = 0.5, size = 2) +
  theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
  geom_line(aes(x = quantile, y = seq(0, 1 , by = 0.1)  , group = 1), color = "blue", size = 2, alpha = 0.5) +
  scale_x_discrete(name ="% of the Data Set",
                   labels=c("0%", "10%","20%","30%", "40%", "50%", "60%","70%","80%", "90%", "100%"))

但是，我收到一条错误消息：

  Error: Aesthetics must be either length 1 or the same as the data (10): x, y, group

我已阅读与此类错误相关的帖子，通常该错误意味着在美学中调用的变量不存在于原始数据框中。但这里不是这样。

我也试过这段代码，但它也返回相同的错误消息：

Gain$index <- row.names(Gain)


ggplot(Gain ) +
  geom_area(aes(x = index, y = Cumsum_Positives, group = 1), color = "red", fill = "red", alpha = 0.5, size = 2) +
  theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
  geom_line(aes(x = quantile, y = seq(0, 1 , by = 0.1)  , group = 1), color = "blue", size = 2, alpha = 0.5) +
  scale_x_discrete(name ="% of the Data Set",
                   labels=c("0%", "10%","20%","30%", "40%", "50%", "60%","70%","80%", "90%", "100%"))

您的建议将不胜感激。

【问题讨论】：

标签： r ggplot2 aesthetics

【解决方案1】：

您的数据长度为 10，而 geom_line 中的 y 美学长度为 11。

seq(0, 1 , by = 0.1)
[1] 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

试试seq(0,0.9,by=0.1) 或seq(0.1,1,by=0.1)

【讨论】：

【解决方案2】：

如果您的目标是从 (x = 0, y = 0) 到 (x = 0.9, y = 1) 画一条线，您也可以将 geom_line 替换为 geom_abline：

geom_abline(slope = 1/9,
            intercept = -0.109,
            color = "blue",
            size = 2,
            alpha = 0.5) +

【讨论】：