如何将数据框中列的数据类型从Char

Question

我正在使用RStudio弄乱R中的某些列，并试图将其中一列的数据类型从Char更改为Date。

我使用了一些选项，而最接近的是

data$Date <- as.Date(as.character(data$Date))

尽管这似乎也不起作用，因为它会将列的值更改为一些奇怪的值

即来自

类似

我不太清楚为什么转换不起作用。

这是我到目前为止的代码

# load the tidyverse library
library("tidyverse")
setwd("C:/Users/ibrahim.cetinkaya/OneDrive - NTT/Desktop/data")
##################### Part A #####################
# data files (you need to specify the paths of the CSV files (e.g. relativeor absolute) )
files <- c("data/201808.csv",
       "data/201809.csv",
       "data/201810.csv",
       "data/201811.csv",
       "data/201812.csv",
       "data/201901.csv",
       "data/201902.csv",
       "data/201903.csv",
       "data/201904.csv",
       "data/201905.csv",
       "data/201906.csv",
       "data/201908.csv"
)

#Concatenate into one data frame. 
data <- data.frame()
for (i in 1:length(files)){
  temp <- read_csv(files[i], skip = 7)
  data <- rbind(data, temp)
}
#View to verify
view(data)

#Part 2
#Remove vairables which have no data at all (All the data are na's)
#Remove variables that doesn't have adequate data (70% of the number of records are NA's)
data <- data[rowMeans(is.na(data))<=0.9,]
view(data)


#Change the column names to have no spaces between the words

names(data) <- gsub(" ", "_", names(data))
view(data)


#Convert Date to date type

#df2 <- data %>% mutate_at(vars(data), as.Date, format="%m-%d-%Y")

#data %>% mutate(data$Date==as.Date(Date, format = "%m.%d.%Y"))
data$Date <- as.Date(as.character(data$Date))
#^^^ This doesn't seem to be working properly ^^^


#Checking if it worked
typeof(data$Date)
view(data)

任何建议将不胜感激。 我希望能够更改数据类型，然后提取月份并将其用于对框架中的其他一些数据进行分组。

Answer 1

使用

data$Date <- as.Date(data$date, "%m/%d/%Y")

然后提取月份

data$Month <- format(data$Date, "%m")

---

我们也可以使用lubridate

data$date <- lubridate::mdy(data$date)

，然后使用month提取月份。

data$month <- month(data$date)

---

并带有anytime

data$Date <- anytime::anydate(data$Date)