按日期对数据框分组:解决缺少时间段的错误

时间:2017-08-31 14:21:46

标签: r dataframe dplyr lubridate tidyverse

我已经确定,如果不是我自己创建的,几周前在StackOverflow上从一个慷慨的响应者那里得到的一些好的代码就可以解决这个问题了,今天我可以使用一些新的帮助。

示例数据(下面称为对象eh):

    ID        2013-03-20 2013-04-09 2013-04-11 2013-04-17 2013-04-25 2013-05-15 2013-05-24 2013-05-25 2013-05-26
    5167f          0          0          0          0          0          0          0          0          0
    1214m          0          0          0          0          0          0          0          0          0
    1844f          0          0          0          0          0          0          0          0          0
    2113m          0          0          0          0          0          0          0          0          0
    2254m          0          0          0          0          0          0          0          0          0
    2721f          0          0          0          0          0          0          0          0          0
    3121f          0          0          0          0          0          0          0          0          0
    3486f          0          0          0          0          0          0          0          0          0
    3540f          0          0          0          0          0          0          0          0          0
    4175m          0          0          0          0          0          0          0          0          0

我需要能够将0s1s分组到各自列日期的时间段(例如,每1,2,3或4周)。每当1在特定日期范围(Period)内至少失一次,那么1中的ID汇总Period0 1}},否则)。

我从1周的汇总例程开始作为例子。我的主要问题是,在时间序列Periods"2013-03-20"期间,生成的最终输出缺少一些可能的1周"2015-12-31"

请注意,在此示例输出中,其中行用于唯一IDs,列用于唯一PeriodsPeriods 2,5,7和9如何丢失:

    1   3   4   6   8   10  11  12  13  14
    0   0   0   0   0   0   0   0   0   0
    0   0   0   0   0   0   0   0   0   0
    0   0   0   0   0   0   0   0   0   0
    0   0   0   0   0   0   0   0   0   0
    0   0   0   0   0   0   0   0   0   0
    0   0   0   0   0   0   0   0   0   0

以下是对原始数据框进行分组的完整例程(参见上面共享的示例数据):

    #Convert to data table from original data frame, eh
    dt <- as.data.table(eh)

    #One week summarized encounter histories
    dt_merge <- data_frame(
      # Create a column showing the beginning date
      Date1 = seq(from = ymd("2013-03-20"), to = ymd("2015-12-31"), by = "1 week")) %>%
      # Create  a column showing the end date of each period
      mutate(Date2 = lead(Date1)) %>%
      # Adjust Date1
      mutate(Date1 = if_else(Date1 == ymd("2013-03-20"), Date1, Date1 + 1)) %>%
      # Remove the last row
      drop_na(Date2) %>%
      # Create date list
      mutate(Dates = map2(Date1, Date2, function(x, y){ seq(x, y, by = "day") })) %>%
      unnest() %>%
      # Create Group ID
      mutate(RunID = group_indices_(., dots. = c("Date1", "Date2"))) %>%
      # Create Period ID
      mutate(Period = paste0(RunID)) %>%
      # Add a column showing Month
      mutate(Month = month(Dates)) %>%
      # Add a column showing Year
      mutate(Year = year(Dates)) %>%
      # Add a column showing season
      mutate(Season = case_when(
        Month %in% 3:5            ~ "Spring",
        Month %in% 6:8            ~ "Summer",
        Month %in% 9:11           ~ "Fall",
        Month %in% c(12, 1, 2)    ~ "Winter",
        TRUE                      ~ NA_character_
      )) %>%
      # Combine Season and Year
      mutate(SeasonYear = paste0(Season, Year)) %>%
      select(-Date1, -Date2, -RunID)
    dt2 <- dt %>%
      # Reshape the data frame
      gather(Date, Value, -ID) %>%
      # Convert Date to date class
      mutate(Date = ymd(Date)) %>%
      # Join dt_merge
      left_join(dt_merge, by = c("Date" = "Dates")) 
    one.week <- dt2 %>%
      group_by(ID, Period) %>%
      summarise(Value = max(Value)) %>%
      spread(Period, Value)

    #Finished product
    one.week <- as.data.frame(one.week)

    #Missing weeks 2, 5, 7, and 9...
    one.week

有人可以帮我理解我哪里出错吗?提前谢谢!

-AD

1 个答案:

答案 0 :(得分:2)

这种情况正在发生,因为eh数据中缺少这几周。例如,如果您查看构成第2周的日期:

dt_merge %>%
  filter(Period == 2)
#> # A tibble: 7 x 6
#>        Dates Period Month  Year Season SeasonYear
#>       <date>  <chr> <dbl> <dbl>  <chr>      <chr>
#> 1 2013-03-28      2     3  2013 Spring Spring2013
#> 2 2013-03-29      2     3  2013 Spring Spring2013
#> 3 2013-03-30      2     3  2013 Spring Spring2013
#> 4 2013-03-31      2     3  2013 Spring Spring2013
#> 5 2013-04-01      2     4  2013 Spring Spring2013
#> 6 2013-04-02      2     4  2013 Spring Spring2013
#> 7 2013-04-03      2     4  2013 Spring Spring2013

您可以看到这些日期都不在eh的列中,从2013-03-20跳到2013-04-09。由于您在创建left_join时使用dt2,因此只保留eh中的日期(以及周数)。

可以使用 tidyr 包中的complete()来更正此问题,以创建ID和日期的缺失组合。

dt2 <- dt %>%
  # Reshape the data frame
  gather(Date, Value, -ID) %>%
  # Convert Date to date class
  mutate(Date = ymd(Date)) %>%
  # Create missing ID/Date combinations
  complete(ID, Date = dt_merge$Dates) %>%
  # Join dt_merge
  left_join(dt_merge, by = c("Date" = "Dates"))
one.week <- dt2 %>%
  mutate(Period = as.numeric(Period)) %>%
  group_by(ID, Period) %>%
  summarise(Value = max(Value, na.rm = TRUE)) %>%
  spread(Period, Value)
one.week
#> # A tibble: 10 x 146
#> # Groups:   ID [10]
#>       ID   `1`   `2`   `3`   `4`   `5`   `6`   `7`   `8`   `9`  `10`  `11`
#>  * <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#>  1 1214m     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  2 1844f     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  3 2113m     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  4 2254m     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  5 2721f     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  6 3121f     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  7 3486f     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  8 3540f     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#>  9 4175m     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#> 10 5167f     0  -Inf     0     0  -Inf     0  -Inf     0  -Inf     0  -Inf
#> # ... with 134 more variables: `12` <dbl>, `13` <dbl>, `14` <dbl>,
#> #   `15` <dbl>, `16` <dbl>, `17` <dbl>, `18` <dbl>, `19` <dbl>,
#> #   `20` <dbl>, `21` <dbl>, `22` <dbl>, `23` <dbl>, `24` <dbl>,
#> #   `25` <dbl>, `26` <dbl>, `27` <dbl>, `28` <dbl>, `29` <dbl>,
#> #   `30` <dbl>, `31` <dbl>, `32` <dbl>, `33` <dbl>, `34` <dbl>,
#> #   `35` <dbl>, `36` <dbl>, `37` <dbl>, `38` <dbl>, `39` <dbl>,
#> #   `40` <dbl>, `41` <dbl>, `42` <dbl>, `43` <dbl>, `44` <dbl>,
#> #   `45` <dbl>, `46` <dbl>, `47` <dbl>, `48` <dbl>, `49` <dbl>,
#> #   `50` <dbl>, `51` <dbl>, `52` <dbl>, `53` <dbl>, `54` <dbl>,
#> #   `55` <dbl>, `56` <dbl>, `57` <dbl>, `58` <dbl>, `59` <dbl>,
#> #   `60` <dbl>, `61` <dbl>, `62` <dbl>, `63` <dbl>, `64` <dbl>,
#> #   `65` <dbl>, `66` <dbl>, `67` <dbl>, `68` <dbl>, `69` <dbl>,
#> #   `70` <dbl>, `71` <dbl>, `72` <dbl>, `73` <dbl>, `74` <dbl>,
#> #   `75` <dbl>, `76` <dbl>, `77` <dbl>, `78` <dbl>, `79` <dbl>,
#> #   `80` <dbl>, `81` <dbl>, `82` <dbl>, `83` <dbl>, `84` <dbl>,
#> #   `85` <dbl>, `86` <dbl>, `87` <dbl>, `88` <dbl>, `89` <dbl>,
#> #   `90` <dbl>, `91` <dbl>, `92` <dbl>, `93` <dbl>, `94` <dbl>,
#> #   `95` <dbl>, `96` <dbl>, `97` <dbl>, `98` <dbl>, `99` <dbl>,
#> #   `100` <dbl>, `101` <dbl>, `102` <dbl>, `103` <dbl>, `104` <dbl>,
#> #   `105` <dbl>, `106` <dbl>, `107` <dbl>, `108` <dbl>, `109` <dbl>,
#> #   `110` <dbl>, `111` <dbl>, ...

如果给定周内没有该ID的值,则返回-Inf。或者,不是使用NA填充缺失值,而是使用complete(ID, Date = dt_merge$Dates, fill = list(Value = 0))填充,例如0。这将使任何未观察到的ID和日期组合的值变量为0.