我有以下示例
id <- c("a","b","a","b","a","a","a","a","b","b","c")
SOG <- c(4,4,0,0,0,0,0,0,0,0,9)
data <- data.frame(id,SOG)
我希望在新列中SOG == 0时的累积值。 使用以下代码
tmp <- rle(SOG) #run length encoding:
tmp$values <- tmp$values == 0 #turn values into logicals
tmp$values[tmp$values] <- cumsum(tmp$values[tmp$values]) #cumulative sum of TRUE values
inverse.rle(tmp) #inverse the run length encoding
我创建了列&#34;停止&#34;:
data$Stops <- inverse.rle(tmp)
我可以进去:
[1] 0 0 1 1 1 1 1 1 1 1 0
但我想改为
[1] 0 0 1 2 3 3 3 3 4 4 0
我的意思是当因素的水平&#34; id&#34;与前一行不同,我想跳到下一行&#34;停止&#34;第(i + 1)。
答案 0 :(得分:4)
查看dplyr
包
library(dplyr)
data %>%
mutate(
Stops = ifelse(
SOG > 0,
0,
cumsum(SOG == 0 & lag(id) != id)
)
)
答案 1 :(得分:1)
我们可以尝试
library(data.table)
setDT(data1)[, v1 := if(all(!SOG)) c(TRUE, id[-1]!= id[-.N]) else
rep(FALSE, .N), .(grp = rleid(SOG))][,cumsum(v1)*(!SOG)]
#[1] 0 0 1 2 3 3 3 3 4 4 0 0 0 0 5 5 0 6 6 0
使用旧数据
setDT(data)[, v1 := if(all(!SOG)) c(TRUE, id[-1]!= id[-.N])
else rep(FALSE, .N), .(grp = rleid(SOG))][,cumsum(v1)*(!SOG)]
#[1] 0 0 1 2 3 3 3 3 4 4 0
id <- c("a","b","a","b","a","a","a","a","b","b","c","a","a","a","a","a","a","a","a", "a")
SOG <- c(4,4,0,0,0,0,0,0,0,0,9,1,5,3,0,0,4,0,0,1)
data1 <- data.frame(id, SOG, stringsAsFactors=FALSE)