创建连续值的组名

Question

看起来很容易完成，无法找到更简单的方法。我在x下面有一个向量，需要为连续的值创建组名。我的尝试是使用rle，更好的主意？

# data

x <- c(1,1,1,2,2,2,3,2,2,1,1)

# make groups

rep(paste0("Group_", 1:length(rle(x)$lengths)), rle(x)$lengths)

# [1] "Group_1" "Group_1" "Group_1" "Group_2" "Group_2" "Group_2" "Group_3" "Group_4"

# [9] "Group_4" "Group_5" "Group_5"

Answer 1

使用diff和cumsum：paste0("Group_", cumsum(c(1, diff(x) != 0)))#[1] "Group_1" "Group_1" "Group_1" "Group_2" "Group_2" "Group_2" "Group_3" "Group_4" "Group_4" "Group_5" "Group_5"（如果您的值是浮点值，则可能必须避免!=使用，而是使用公差。）

Answer 2

groupdata2中的group（）可以使用l_starts方法根据组起点列表创建组。通过设置n为auto，它会自动查找组开始：x <- c(1,1,1,2,2,2,3,2,2,1,1)groupdata2::group(x, n = "auto", method = "l_starts")## # A tibble: 11 x 2## # Groups:&nbsp; &nbsp;.groups [5]##&nbsp; &nbsp; &nbsp;data .groups##&nbsp; &nbsp; <dbl> <fct>&nbsp;&nbsp;##&nbsp; 1&nbsp; &nbsp; &nbsp;1 1&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 2&nbsp; &nbsp; &nbsp;1 1&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 3&nbsp; &nbsp; &nbsp;1 1&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 4&nbsp; &nbsp; &nbsp;2 2&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 5&nbsp; &nbsp; &nbsp;2 2&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 6&nbsp; &nbsp; &nbsp;2 2&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 7&nbsp; &nbsp; &nbsp;3 3&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 8&nbsp; &nbsp; &nbsp;2 4&nbsp; &nbsp; &nbsp;&nbsp;##&nbsp; 9&nbsp; &nbsp; &nbsp;2 4&nbsp; &nbsp; &nbsp;&nbsp;## 10&nbsp; &nbsp; &nbsp;1 5&nbsp; &nbsp; &nbsp;&nbsp;## 11&nbsp; &nbsp; &nbsp;1 5&nbsp; &nbsp; &nbsp;还有一个differs_from_previous()函数可以找到与先前值相差某个阈值的值或值的索引。# The values to start groups atdiffers_from_previous(x, threshold = 1,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; direction = "both")## [1] 2 3 2 1# The indices to start groups atdiffers_from_previous(x, threshold = 1,&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; direction = "both",&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return_index = TRUE)## [1] 4 7 8 10