按值对 geom_bar ggplot2 中的条形重新排序

我正在尝试制作一个条形图，其中的图是从miRNA与最高的value to the miRNA与最低的。为什么我的代码不起作用？

> head(corr.m)

        miRNA         variable value
1    mmu-miR-532-3p      pos     7
2    mmu-miR-1983        pos    75
3    mmu-miR-301a-3p     pos    70
4    mmu-miR-96-5p       pos     5
5    mmu-miR-139-5p      pos    10
6    mmu-miR-5097        pos    47

ggplot(corr.m, aes(x=reorder(miRNA, value), y=value, fill=variable)) + 
  geom_bar(stat="identity")

您的代码工作正常，只是条形图是从低到高排序的。当您想要从高到低对条形进行排序时，您必须添加-之前签名value:

ggplot(corr.m, aes(x = reorder(miRNA, -value), y = value, fill = variable)) + 
  geom_bar(stat = "identity")

这使：

使用数据：

corr.m <- structure(list(miRNA = structure(c(5L, 2L, 3L, 6L, 1L, 4L), .Label = c("mmu-miR-139-5p", "mmu-miR-1983", "mmu-miR-301a-3p", "mmu-miR-5097", "mmu-miR-532-3p", "mmu-miR-96-5p"), class = "factor"),
                         variable = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "pos", class = "factor"),
                         value = c(7L, 75L, 70L, 5L, 10L, 47L)),
                    class = "data.frame", row.names = c("1", "2", "3", "4", "5", "6"))