是否使用dplyr向分组数据添加行?
我的数据采用data.frame格式,如以下示例数据:是否使用dplyr向分组数据添加行?,r,dataframe,dplyr,R,Dataframe,Dplyr,我的数据采用data.frame格式,如以下示例数据: data <- structure(list(Article = structure(c(1L, 1L, 3L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 1L, 2L, 1L, 2L, 1L ), .Label = c("10004", "10006", "10007"), class = "factor"), Demand = c(26L, 780L, 2
data <-
structure(list(Article = structure(c(1L, 1L, 3L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 1L, 2L, 1L, 2L, 1L
), .Label = c("10004", "10006", "10007"), class = "factor"),
Demand = c(26L, 780L, 2L, 181L, 228L, 214L, 219L, 291L, 104L,
72L, 155L, 237L, 182L, 148L, 52L, 227L, 2L, 355L, 2L, 432L,
1L, 156L), Week = c("2013-W01", "2013-W01", "2013-W01", "2013-W01",
"2013-W01", "2013-W02", "2013-W02", "2013-W02", "2013-W02",
"2013-W02", "2013-W03", "2013-W03", "2013-W03", "2013-W03",
"2013-W03", "2013-W04", "2013-W04", "2013-W04", "2013-W04",
"2013-W04", "2013-W04", "2013-W04")), .Names = c("Article",
"Demand", "Week"), class = "data.frame", row.names = c(NA, -22L))
我试过了
WeekSums %>%
group_by(Article) %>%
if(n()< 4) rep(rbind(c(Article,NA,NA)), 4 - n() )
WeekSums%>%
按(物品)分组%>%
if(n()<4)rep(rbind(c(Article,NA,NA)),4-n()
但这不起作用。在我最初的方法中,我通过为每篇文章将第1-4周的数据帧与我的rawdata文件合并来解决这个问题。这样,我每篇文章有4周(行),但使用for循环的实现效率非常低,因此我尝试使用dplyr(或任何其他更高效的包/函数)也这样做。任何建议都将不胜感激 没有dplyr,可以这样做:
Article Week WeekDemand
1 10004 2013-W01 1215
2 10004 2013-W02 900
3 10004 2013-W03 774
4 10004 2013-W04 1170
5 10006 2013-W01 0
6 10006 2013-W02 0
7 10006 2013-W03 0
8 10006 2013-W04 5
9 10007 2013-W01 2
10 10007 2013-W02 0
11 10007 2013-W03 0
12 10007 2013-W04 0
as.data.frame(xtabs(Demand ~ Week + Article, data))
data %>% xtabs(formula = Demand ~ Week + Article) %>% as.data.frame()
给予:
Week Article Freq
1 2013-W01 10004 1215
2 2013-W02 10004 900
3 2013-W03 10004 774
4 2013-W04 10004 1170
5 2013-W01 10006 0
6 2013-W02 10006 0
7 2013-W03 10006 0
8 2013-W04 10006 5
9 2013-W01 10007 2
10 2013-W02 10007 0
11 2013-W03 10007 0
12 2013-W04 10007 0
这可以重写为magrittr或dplyr管道,如下所示:
Article Week WeekDemand
1 10004 2013-W01 1215
2 10004 2013-W02 900
3 10004 2013-W03 774
4 10004 2013-W04 1170
5 10006 2013-W01 0
6 10006 2013-W02 0
7 10006 2013-W03 0
8 10006 2013-W04 5
9 10007 2013-W01 2
10 10007 2013-W02 0
11 10007 2013-W03 0
12 10007 2013-W04 0
as.data.frame(xtabs(Demand ~ Week + Article, data))
data %>% xtabs(formula = Demand ~ Week + Article) %>% as.data.frame()
如果需要广泛形式的解决方案,可以省略结尾处的
as.data.frame()
。我想我会提供一个dplyr
式的解决方案
- 使用
生成要查找的成对组合李>expand.grid()
- 使用
加入需求数据(用NAs填充其余数据)left\u join()
full\u data对于这种情况,您还可以使用dcast
和melt
library(dplyr)
library(reshape2)
data %>%
dcast(Article ~ Week, value.var = "Demand", fun.aggregate = sum) %>%
melt(id = "Article") %>%
arrange(Article, variable)
由于dplyr
正在积极开发中,我想我会发布一个更新,其中也包含tidyr
:
library(dplyr)
library(tidyr)
data %>%
expand(Article, Week) %>%
left_join(data) %>%
group_by(Article, Week) %>%
summarise(WeekDemand = sum(Demand, na.rm=TRUE))
产生:
Article Week WeekDemand
1 10004 2013-W01 1215
2 10004 2013-W02 900
3 10004 2013-W03 774
4 10004 2013-W04 1170
5 10006 2013-W01 0
6 10006 2013-W02 0
7 10006 2013-W03 0
8 10006 2013-W04 5
9 10007 2013-W01 2
10 10007 2013-W02 0
11 10007 2013-W03 0
12 10007 2013-W04 0
使用tidyr>=0.3.1,现在可以写成:
data %>%
complete(Article, Week) %>%
group_by(Article, Week) %>%
summarise(Demand = sum(Demand, na.rm = TRUE))
xtabs
使用指定的公式创建一个类为“table”
的对象,其维度为右侧变量,单元格为左侧变量之和,如果单元格为空,则为零as.data.frame
应用于表格时,会将其重塑为长格式。感谢您演示解决此问题的另一种方法!我必须承认我喜欢xtabs
解决方案的简单性,但这也会产生期望的结果(+1)
Article Week WeekDemand
1 10004 2013-W01 1215
2 10004 2013-W02 900
3 10004 2013-W03 774
4 10004 2013-W04 1170
5 10006 2013-W01 0
6 10006 2013-W02 0
7 10006 2013-W03 0
8 10006 2013-W04 5
9 10007 2013-W01 2
10 10007 2013-W02 0
11 10007 2013-W03 0
12 10007 2013-W04 0
data %>%
complete(Article, Week) %>%
group_by(Article, Week) %>%
summarise(Demand = sum(Demand, na.rm = TRUE))