我有这个数据帧

um dois tres

1.2 1.9 0.1

1.2 1.1 2

2.2 1.2 0.4

3.0 1.8 2.6

我需要在同一函数中计算数据帧的均值，方差和偏度。我把功能分开了。有什么建议？

mean <- function(x){

sum(x)/length(x)

}

variance <- function(x){

n <- length(x)

m <- mean(x)

(1/(n-1))*sum((x-m)^2)

}

skewness <- function(x) {

n <- length(x)

v <- var(x)

m <- mean(x)

third.moment <- (1/(n - 2))*sum((x - m)^3)

third.moment/(var(x)^(3/2))

}

解决办法：dput(data)

structure(list(um = c(1.2, 1.2, 2.2, 3), dois = c(1.9, 1.1, 1.2, 1.8), tres = c(0.1, 2, 0.4, 2.6)), class = "data.frame", row.names = c(NA,-4L))

# to use the function skewnewss install and load the package e1071

library(e1071)

sapply(data, function(x) c(means = mean(x), vars = var(x), skews = skewness(x)))

对于每个输入列，输出一次性生成所需的计算：

um dois tres

means 1.9000000 1.5000000 1.27500000

vars 0.7600000 0.1666667 1.47583333

skews 0.2535648 0.0000000 0.05788459