网页抓取有奇怪的日期格式，需要转换。 “charToDate(x) 中的错误：字符串不是标准的明确格式”答案

【问题标题】：Web-scraping has weird format of date, need to convert. "Error in charToDate(x) : character string is not in a standard unambiguous format"网页抓取有奇怪的日期格式，需要转换。 “charToDate(x) 中的错误：字符串不是标准的明确格式”
【发布时间】：2021-01-20 15:46:28
【问题描述】：

我每天都在尝试抓取这个网站。 https://www.basketball-reference.com/boxscores/?month=9&day=30&year=2020 如您所见，日期格式不正确，我不知道如何让 R 将其识别为日期。

到目前为止，这是我的代码：

url <- "https://www.basketball-reference.com/boxscores/"

timevalues <- seq(as.Date("month=10&day=2&year=2020"), as.Date("month=10&day=2&year=2020"), by = "day")
head(timevalues)

charToDate(x) 中的错误：字符串不是标准的明确格式

【问题讨论】：

标签： r web-scraping as.date

【解决方案1】：

您不能像这样生成序列（或日期）。这是使用 lubridate 包的解决方案

library(lubridate)

url <- "https://www.basketball-reference.com/boxscores/"

my_dates <- seq(as.Date("2020-09-25"), as.Date("2020-10-05"), by = "day")

urls <- paste0(url, 
               "?month=", month(my_dates),
               "&day=", day(my_dates), 
               "&year=", year(my_dates))

urls
#>  [1] "https://www.basketball-reference.com/boxscores/?month=9&day=25&year=2020"
#>  [2] "https://www.basketball-reference.com/boxscores/?month=9&day=26&year=2020"
#>  [3] "https://www.basketball-reference.com/boxscores/?month=9&day=27&year=2020"
#>  [4] "https://www.basketball-reference.com/boxscores/?month=9&day=28&year=2020"
#>  [5] "https://www.basketball-reference.com/boxscores/?month=9&day=29&year=2020"
#>  [6] "https://www.basketball-reference.com/boxscores/?month=9&day=30&year=2020"
#>  [7] "https://www.basketball-reference.com/boxscores/?month=10&day=1&year=2020"
#>  [8] "https://www.basketball-reference.com/boxscores/?month=10&day=2&year=2020"
#>  [9] "https://www.basketball-reference.com/boxscores/?month=10&day=3&year=2020"
#> [10] "https://www.basketball-reference.com/boxscores/?month=10&day=4&year=2020"
#> [11] "https://www.basketball-reference.com/boxscores/?month=10&day=5&year=2020"

【讨论】：

【解决方案2】：

我们可以使用glue来创建

library(lubridate)
url <- "https://www.basketball-reference.com/boxscores/"
my_dates <- seq(as.Date("2020-09-25"), as.Date("2020-10-05"), by = "day")
urls <- glue::glue("{url}?month={month(my_dates)}&day={day(my_dates)}",
               "&year={year(my_dates)}")

-输出

#https://www.basketball-reference.com/boxscores/?month=9&day=25&year=2020
#https://www.basketball-reference.com/boxscores/?month=9&day=26&year=2020
#https://www.basketball-reference.com/boxscores/?month=9&day=27&year=2020
#https://www.basketball-reference.com/boxscores/?month=9&day=28&year=2020
#https://www.basketball-reference.com/boxscores/?month=9&day=29&year=2020
#https://www.basketball-reference.com/boxscores/?month=9&day=30&year=2020
#https://www.basketball-reference.com/boxscores/?month=10&day=1&year=2020
#https://www.basketball-reference.com/boxscores/?month=10&day=2&year=2020
#https://www.basketball-reference.com/boxscores/?month=10&day=3&year=2020
#https://www.basketball-reference.com/boxscores/?month=10&day=4&year=2020
#https://www.basketball-reference.com/boxscores/?month=10&day=5&year=2020

【讨论】：