R 计算在多个变量上具有特定值的组数
我有一个数据框,例如:R 计算在多个变量上具有特定值的组数,r,grouping,R,Grouping,我有一个数据框,例如: city <- c("a","a","b","b","c","c","c","c","d","e","e","f") x <- c(0,0,0,1,1,1,0,0,0,1,1,1) y <- c(1,1,0,0,0,1,1,0,0,1,0,1) z <- c(1,0,0,0,0,0,0,0,0,0,1,0) k <- c(1,1,0,0,0,1,0,0,1,0,0,0) df <- data.frame(city, x, y, z,
city <- c("a","a","b","b","c","c","c","c","d","e","e","f")
x <- c(0,0,0,1,1,1,0,0,0,1,1,1)
y <- c(1,1,0,0,0,1,1,0,0,1,0,1)
z <- c(1,0,0,0,0,0,0,0,0,0,1,0)
k <- c(1,1,0,0,0,1,0,0,1,0,0,0)
df <- data.frame(city, x, y, z, k)
但是,我想知道是否有可能对我的数据帧中的所有假人执行此操作,以获得如下结果:
var count
x 4
y 4
z 2
k 3
其中,每个虚拟变量等于1(计数列)的城市数量,而不必对样本中的所有虚拟分别进行计算
谢谢你的帮助 使用
数据。表:
library(data.table)
setDT(df)
df[, lapply(.SD, max), city][, colSums(.SD), .SDcols = -1]
x y z k
4 4 2 3
使用dplyr
和tidyr
:
library(dplyr)
library(tidyr)
df %>%
gather(k, v, -1) %>%
filter(v == 1) %>%
group_by(k) %>%
summarise(cnt = n_distinct(city))
结果是:
# A tibble: 4 x 2
k cnt
<chr> <int>
1 k 3
2 x 4
3 y 4
4 z 2
#一个tible:4 x 2
碳纳米管
1 k3
2 x 4
3 y 4
4 z 2
R基础:
colSums(rowsum(df[, -1], df[, 1]) > 0)
#x y z k
#4 4 2 3
不知道这个函数rowsum()
!在这里提出的其他解决方案中,我认为这是一个更简单的解决方案。将stack
包裹在它周围,就可以得到预期的输出格式
colSums(rowsum(df[, -1], df[, 1]) > 0)
#x y z k
#4 4 2 3