列出数据框子集中的所有变量（及其比例）

Question

对于包含一组经度和纬度坐标对以及对象到达它们的时间的示例数据框：

bout <- structure(list(Date = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = "02/02/2013", class = "factor"),
Time = structure(1:30, .Label = c("07:55:40", "07:55:50",
"07:56:00", "07:56:10", "07:56:20", "07:56:30", "07:56:40",
"07:56:50", "07:57:00", "07:57:10", "07:57:20", "07:57:30",
"07:57:40", "07:57:50", "07:58:00", "07:58:10", "07:58:20",
"07:58:30", "07:58:40", "07:58:50", "07:59:00", "07:59:10",
"07:59:20", "07:59:30", "07:59:40", "07:59:50", "08:00:00",
"08:00:10", "08:00:20", "08:00:30"), class = "factor"), Axis1 = c(0L,
0L, 100L, 500L, 233L, 155L, 60L, 0L, 0L, 115L, 80L, 878L,
158L, 0L, 13L, 0L, 0L, 25L, 10L, 45L, 33L, 43L, 655L, 498L,
41L, 151L, 404L, 436L, 28L, 0L), Latitude = c(56.52289678,
56.52291659, 56.52292762, 56.52295108, 56.52292694, 56.52292513,
56.5229401, 56.52294825, 56.52295531, 56.52296413, 56.52296976,
56.52292374, 56.52293053, 56.52292422, 56.52289636, 56.52288866,
56.52293357, 56.52290114, 56.5228365, 56.52280237, 56.52279844,
56.52281107, 56.52282589, 56.52279711, 56.52277008, 56.52278785,
56.52279951, 56.52269176, 56.52270186, 56.52269016), Longitude = c(-2.56573101,
-2.56578171, -2.56579263, -2.56578099, -2.56575181, -2.56574877,
-2.56575947, -2.5657653, -2.56577941, -2.56577104, -2.56577004,
-2.56576048, -2.56575937, -2.56582402, -2.56585538, -2.56579373,
-2.56572003, -2.56568263, -2.56568237, -2.56570739, -2.56570637,
-2.56571299, -2.56572322, -2.56566835, -2.56566237, -2.56569353,
-2.56571833, -2.56563307, -2.56565902, -2.56565666), area = structure(c(1L,
1L, 2L, 2L, 2L, 2L, 3L, 4L, 5L, 6L, 6L, 7L, 7L, 7L, 8L, 9L,
10L, 11L, 2L, 2L, 6L, 6L, 6L, 6L, 12L, 13L, 13L, 13L, 13L,
13L), .Label = c("E456", "E457", "E460", "E461", "E462",
"E463", "E465", "E468", "E469", "E470", "E471", "E478", "E479"
), class = "factor"), bout = c(0L, 0L, 1L, 1L, 1L,
1L, 1L, 0L, 0L, 2L, 2L, 2L, 2L, 2L, 2L, 0L, 0L, 0L, 3L, 3L,
3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 0L)), .Names = c("Date",
"Time", "Axis1", "Latitude", "Longitude", "area", "bout"
), class = "data.frame", row.names = c(NA, -30L))

我想创建一个关于 activity 的摘要变量。到目前为止我有：

bout$Date <- as.Date(bout$Date, origin = "1970-01-01", format = "%d/%m/%Y")
library(chron)
bout$Time <- times(as.character(bout$Time))

my.stats <- function(x) {
    min.Date <- min(x$Date)
    min.Time <- min(x$Time)
    max.Time <- max(x$Time)
    time.bout <- max.Time - min.Time
    return(data.frame(min.Date, min.Time, max.Time, time.bout))
}

library(plyr)
ddply(bout, .(bout), my.stats)

在这些变量之后，我还想要每个 activity 发生的区域列表。

我通常会使用：

unique(unlist(bout$area, use.names = FALSE))

但我想知道如何报告在每个领域花费的时间比例？理想情况下，我希望将其集成到上面的功能中。每个 activity 不应超过 10 个区域（因此当列出的区域较少时，我对空白很满意）。

例如（只显示两个区域）：

bout     area.1      time.area.1      area.2      time.area.2 
2        E457        0.80             E460        0.20       
3        E465        0.50             E463        0.33

如有任何想法，我们将不胜感激。

Answer 1

对于您要执行的操作，上面带有空白的矩阵是一种相当笨重的样式，并且很难（呃）创建。以下可能更有用（并捕获相同的信息）。

设置数据：

bout$StartTime <- times(as.character(bout$Time))
bout$EndTime <- bout$StartTime + times("00:00:10")

合计

library(data.table)
bout.result <- setDT(bout)[order(bout), list(Date = min(Date), Dur = max(Time) - min(Time)), by = c("bout","area")]

这将为您提供每个独特回合的持续时间，由回合和区域标识。我还复制了您的 min(Date) 符号。如果超过 10 areas/bout，您可以轻松地添加更多行。

比例：

boutPro <- bout.result[, list(boutDur = times(sum(Dur))), by = "bout"]
bout.result <- merge(bout.result,boutPro, by = "bout")
bout.result$prop <- as.numeric(bout.result$Dur/bout.result$boutDur)

结果

bout.result

    bout area       Date      Dur  boutDur       prop
 1:    0 E456 2013-02-02 00:00:20 00:01:20 0.25000000
 2:    0 E461 2013-02-02 00:00:10 00:01:20 0.12500000
 3:    0 E462 2013-02-02 00:00:10 00:01:20 0.12500000
 4:    0 E469 2013-02-02 00:00:10 00:01:20 0.12500000
 5:    0 E470 2013-02-02 00:00:10 00:01:20 0.12500000
 6:    0 E471 2013-02-02 00:00:10 00:01:20 0.12500000
 7:    0 E479 2013-02-02 00:00:10 00:01:20 0.12500000
 8:    1 E457 2013-02-02 00:00:40 00:00:50 0.80000000
 9:    1 E460 2013-02-02 00:00:10 00:00:50 0.20000000
10:    2 E463 2013-02-02 00:00:20 00:01:00 0.33333333
11:    2 E465 2013-02-02 00:00:30 00:01:00 0.50000000
12:    2 E468 2013-02-02 00:00:10 00:01:00 0.16666667
13:    3 E457 2013-02-02 00:00:20 00:01:50 0.18181818
14:    3 E463 2013-02-02 00:00:40 00:01:50 0.36363636
15:    3 E478 2013-02-02 00:00:10 00:01:50 0.09090909
16:    3 E479 2013-02-02 00:00:40 00:01:50 0.36363636

列出数据框子集中的所有变量（及其比例）

List all variables (and their proportions) in a subset of a dataframe

r

plyr