Question

我想按天气类型创建日期范围，添加一个新列以提供该天气的天数，再添加两个列以提供平均温度，然后是“ df”的温度总和

set.seed(121)
df <- data.frame( "Date" = sprintf("%02d-Jan", 1:10), "Type of Weather" = c(rep("Cloudy", 3), rep("Rainy", 2), rep("Cloudy", 4), rep("Sunny", 1)), "Average temperature"= 20:29 )

预期输出：

ndf <- df[, .(Date = paste(Date[1], "to", Date[.N]), weather = Type.of.Weather[1]), rleid(Type.of.Weather) ][, rleid := NULL ][] ndf$Countofdays= c(3,2,4,1) ndf$Averagetemp=c(21,23.5,26.5,29)

Input:

Expected output:

Answer 1

我们可以执行以下操作

parse.date <- function(x) as.POSIXct(x, format = "%d-%b")
df %>%
    mutate(grp = cumsum(c(0, diff(as.numeric(as.factor(Type.of.Weather))) != 0))) %>%
    group_by(grp) %>%
    summarise(
        Countofdays = parse.date(Date[length(Date)]) - parse.date(Date[1]) + 1,
        Date = paste0(Date[1], " to ", Date[length(Date)]),
        weather = unique(Type.of.Weather),
        Averagetemp = mean(Average.temperature)) %>%
    select(Date, weather, Countofdays, Averagetemp)
 ## A tibble: 4 x 4
 #  Date             weather Countofdays Averagetemp
 #  <chr>            <fct>   <time>            <dbl>
 #1 01-Jan to 03-Jan Cloudy  3                  21.0
 #2 04-Jan to 05-Jan Rainy   2                  23.5
 #3 06-Jan to 09-Jan Cloudy  4                  26.5
 #4 10-Jan to 10-Jan Sunny   1                  29.0

样本数据

set.seed(121)
df <- data.frame( "Date" = sprintf("%02d-Jan", 1:10), "Type of Weather" = c(rep("Cloudy", 3), rep("Rainy", 2), rep("Cloudy", 4), rep("Sunny", 1)), "Average temperature"= 20:29 )

汇总数据框并添加新列

1 个答案:

样本数据