如何对字符串中的日期进行排序？

Question

我有几个包含日期的文件名,我需要按数字顺序对它们进行排序,例如:

dates=c("8_18_2016.xlsx","8_25_2016.xlsx","8_4_2016.xlsx")

我想把它整理成:

> dates
"8_4_2016.xlsx"  "8_18_2016.xlsx"  "8_25_2016.xlsx"

谢谢

Answer 1

一种方法是通过创建单独的向量来查找顺序,其中值将转换为日期格式:

dates.order <- order( as.Date( dates, format = "%m_%d_%Y.xlsx" ) )

然后使用它来对原始矢量进行排序:

sorted <- dates[ dates.order ]
sorted
[1] "8_4_2016.xlsx"  "8_18_2016.xlsx" "8_25_2016.xlsx"