我的数据框中的一个列如下所示:
> head(df$col2,n = 50)
[1] "NA, 2015" "November 13, 2014" "September 27, 2014" "October 8, 2014" "December 16, 2013"
[6] "February 8, 2015" "November 2, 2014" "November 30, 2014" "February 18, 2015" "August 22, 2014"
[11] "October 26, 2014" "January 3, 2014" "May 5, 2015" "February 3, 2014" "October 15, 2014"
[16] "September 12, 2014" "April 2, 2014" "April 23, 2015" "November 4, 2014" "January 16, 2014"
[21] "September 28, 2014" "January 14, 2014" "February 13, 2014" "January 17, 2014" "January 4, 2014"
[26] "February 1, 2015" "January 14, 2014" "April 18, 2014" "October 14, 2014" "August 20, 2014"
[31] "January 20, 2014" "April 11, 2015" "July 5, 2014" "November 29, 2013" "March 22, 2014"
[36] "December 29, 2014" "February 18, 2015" "January 13, 2014" "January 5, 2015" "April 19, 2014"
[41] "November 28, 2014" "13 August, 2014" "14 December, 2014" "10 January, 2014" "3 February, 2014"
[46] "17 March, 2014" "3 July, 2014" "17 October, 2014" "28 January, 2014" "10 October, 2014"
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正如你所看到的,除了第一行(我知道是NA,这没问题),mdy和dmy之间有两种不同的日期格式.是否有推荐的方法将所有日期标准化为mdy?
它们都在我的数据框列中列为字符格式.我试过了
> datestest <- as.Date(df$col2),
但我明白了
Error in charToDate(x) : character string is not in a standard unambiguous format
结果是.
该parse_date_time函数lubridate允许您解析与使用"订单"的说法异构格式的载体:
require(lubridate)
x <- c("November 2, 2014", "13 August, 2014")
parse_date_time(x, orders = c("mdy", "dmy"))
[1] "2014-11-02 UTC" "2014-08-13 UTC"
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