使用Reduce()计算R中的百分位数或方差

percentile <- function(data, p) {
  sorted_data <- sort(data)
  n <- length(sorted_data)
  index <- ceiling(p * n / 100)
  return(sorted_data[index])
}

# 示例数据
data <- c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

# 计算第50百分位数（中位数）
median <- Reduce(percentile, init = data, accumulate = TRUE)[-1]
result <- median[length(median)]

variance <- function(data) {
  n <- length(data)
  mean_value <- mean(data)
  squared_diff <- (data - mean_value)^2
  return(sum(squared_diff) / n)
}

# 示例数据
data <- c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

# 计算方差
variance <- Reduce(variance, init = data, accumulate = TRUE)[-1]
result <- variance[length(variance)]