如何重新排列R中矩阵的行

Question

我有以下数据框架：

> agg_2
# A tibble: 3 × 3
  bcs        default_flag pred_default
  <chr>             <dbl>        <dbl>
1 high-score      0.00907       0.0121
2 low-score       0.0345        0.0353
3 mid-score       0.0210        0.0204

我使用以下代码将其绘制为条形图：

barplot(t(as.matrix(agg_2[,-1])),
        main = "Actual Default vs Predicted Default",
        xlab = "Score Category",
        ylab = "Default Rate",
        names.arg = c("High Score", "Low Score", "Mid Score"),
        col = gray.colors(2),
        beside = TRUE)
legend("topleft",
       c("Default", "Pred. Default"),
       fill = gray.colors(2))

它给了我这一点：

我如何重新安排数据框架/矩阵，以便bar plot中的一组bar如下：低分然后Mid Score然后高分？

Answer 1

这是一个潜在的解决方案：

agg_2 <- read.table(text = "bcs        default_flag pred_default
high-score      0.00907       0.0121
low-score       0.0345        0.0353
mid-score       0.0210        0.0204", header = TRUE)

agg_2$bcs <- factor(agg_2$bcs, levels = c("low-score", "mid-score", "high-score"), ordered = TRUE)
agg_2 <- agg_2[order(agg_2$bcs),]

barplot(t(as.matrix(agg_2[,-1])),
        main = "Actual Default vs Predicted Default",
        xlab = "Score Category",
        ylab = "Default Rate",
        names.arg = agg_2$bcs,
        col = gray.colors(2),
        beside = TRUE)
legend("topright",
       c("Default", "Pred. Default"),
       fill = gray.colors(2))

^{在2022-06-21上由 reprex软件包（v2.0.1）}