r - 按日期间隔索引数据帧

Question

我有一个数据框，其中一列包含数百个日期格式的日期，例如：

as.Date(c("2011-08-13","2011-09-13","2010-06-12","2012-09-13","2010-09-13","2012-05-26","2012-07-20"))

现在我只想选择 15.03 < date < 15.8 的行（所有日期在 3 月 15 日到 10 月 15 日之间，不考虑年份）。有没有一种简单的方法来选择（索引）？

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我稍微修改了我接受的答案，如下：

a <- as.Date(c("2011-08-13","2011-09-13","2010-06-12","2012-09-13","2010-09-13","2012-05-26","2012-07-20"))
lower <- as.Date("03-15",format="%m-%d")
upper <- as.Date("08-15",format="%m-%d")
a[format(a,"%m-%d") < format(upper,"%m-%d") & format(a,"%m-%d") > format(lower,"%m-%d")]
[1] "2011-08-13" "2010-06-12" "2012-05-26" "2012-07-20"

Answer 1

在base中，想法是使用函数format：

a <- as.Date(c("2011-08-13","2011-09-13","2010-06-12","2012-09-13","2010-09-13","2012-05-26","2012-07-20"))
lower <- as.Date("2012-03-15")
upper <- as.Date("2012-08-15")
a[format(a,"%m-%d") < format(upper,"%m-%d") & format(a,"%m-%d") > format(lower,"%m-%d")]
[1] "2011-08-13" "2010-06-12" "2012-05-26" "2012-07-20"