我正在尝试从数据框中读取日期列,该数据框存储为字符串|(参见列' DateString'。这就是我的数据的样子:
X. Date_String ASIN Stars positive_rating
1 0 20150430 B00GKKI4IE 5 0
2 1 20150430 B00GKKI4IE 5 0
3 2 20150430 B00GKKI4IE 5 0
4 3 20150429 B00GKKI4IE 5 0
5 4 20150428 B00GKKI4IE 5 0
6 5 20150428 B00GKKI4IE 5 0
这就是我用来格式化这个列的日期
data$date.of.review <- as.Date(data$Date_String, "%Y%m%d")
并收到错误消息
Error in charToDate(x) :
character string is not in a standard unambiguous format
任何想法如何解决?感谢
以下是数据帧的结构:
structure(list(X. = 0:5, Date_String = c(20150430L, 20150430L,
20150430L, 20150429L, 20150428L, 20150428L), ASIN = structure(c(1L,
1L, 1L, 1L, 1L, 1L), .Label = c("B00GKKI4IE", "B00I4OBXWI", "B00IB17BFM",
"B00IN2WD5C", "B00J58F0IA", "B00K7NCS9G", "B00KJEZIBS", "B00KZER5GS",
"B00MK39H68", "B00O1GTTWY"), class = "factor"), Stars = c(5L,
5L, 5L, 5L, 5L, 5L), positive_rating = c(0, 0, 0, 0, 0, 0)), .Names = c("X.",
"Date_String", "ASIN", "Stars", "positive_rating"), row.names = c(NA,
6L), class = "data.frame")
答案 0 :(得分:2)
如果将变量包装在as.character中,则该类为整数.date可以读取它。
sapply(data, class)
data$date.of.review <- as.Date(as.character(data$Date_String), "%Y%m%d")
data