r - as.Date 返回 NA

Question

我有一个非常简单的问题，但不知何故我无法弄清楚问题所在。我想将字符列转换为日期列，以便之后能够创建折线图（x 轴上的日期，y 轴上的 x）。但是，当我尝试转换数据列时，只返回 NA。我已经尝试了其他线程上提供的许多不同的建议，但它仍然不起作用。非常感谢任何帮助！

structure(list(Group.1 = c("April 2020", "December 2019", "February 2020", 
"January 2020", "March 2020", "May 2020", "November 2019", "October 2019"
), x = c(115, 163, 184, 102, 251, 58, 154, 10)), row.names = c(NA, 
-8L), class = "data.frame")
#>         Group.1   x
#> 1    April 2020 115
#> 2 December 2019 163
#> 3 February 2020 184
#> 4  January 2020 102
#> 5    March 2020 251
#> 6      May 2020  58
#> 7 November 2019 154
#> 8  October 2019  10

login_plot$DATE <- as.Date(login_plot$Group.1, format ="%B %Y")

structure(list(Group.1 = c("April 2020", "December 2019", "February 2020", 
"January 2020", "March 2020", "May 2020", "November 2019", "October 2019"
), x = c(115, 163, 184, 102, 251, 58, 154, 10), DATE = structure(c(NA_real_, 
NA_real_, NA_real_, NA_real_, NA_real_, NA_real_, NA_real_, NA_real_
), class = "Date")), row.names = c(NA, -8L), class = "data.frame")

        Group.1   x DATE
1    April 2020 115 <NA>
2 December 2019 163 <NA>
3 February 2020 184 <NA>
4  January 2020 102 <NA>
5    March 2020 251 <NA>
6      May 2020  58 <NA>
7 November 2019 154 <NA>
8  October 2019  10 <NA>

标签： ras.date