用于按列计算 R 数据帧中位数的函数，该 R 数据帧定期对多个数据帧执行

Question

尝试编写一个函数来组合在 R 数据帧上经常使用的多个步骤。目前我堆叠单独的行，这是最低效的。我现在采取的每一步都有一个例子

library(scores)
MscoreIndex <- 3


labMedians <- mapply(median, df[-1], na.rm = T) #calculate the median for each column except 1st
LabGrandMedian <- median(mapply(median, df[-1], na.rm = T),na.rm = T)
labMscore <- as.vector(round(abs(scores_na(labMedians, "mad")), digits = 2)) #calculate mscore by lab
labMscoreIndex <- which(labMscore > MscoreMax) #get the position in the vector that exceeds Mscoremax
df[-1][labMscoreIndex] <- NA # discharge values above threshold by making NA

下面是我的 df 示例

structure(list(Determination_No = 1:6, `2` = c(55.94, 55.7, 56.59, 
56.5, 55.98, 55.93), `3` = c(56.83, 56.54, 56.18, 56.5, 56.51, 
56.34), `4` = c(56.39, 56.43, 56.53, 56.31, 56.47, 56.35), `5` = c(56.32, 
56.29, 56.31, 56.32, 56.39, 56.32), `7` = c(56.48, 56.4, 56.54, 
56.43, 56.73, 56.62), `8` = c(56.382, 56.258, 56.442, 56.258, 
56.532, 56.264), `10` = c(56.3, 56.5, 56.2, 56.5, 56.7, 56.5), 
    `12` = c(56.11, 56.46, 56.1, 56.35, 56.36, 56.37)), class = "data.frame", row.names = c(NA, 
-6L))

我首先尝试使用以下方法获取单个实验室中位数和孙中位数，但出现错误

我试过了。

mediansFunction <- function(x){
              analytemedians <- mapply(median(x[,-1]))
              grandmedian <- median(x[,-1])
              list(analytemedians,grandmedian)
            }

mediansFunction(df)

但我得到“median.default(x[, -1]) 中的错误：需要数字数据”

Answer 1

试试：

mediansFunction <- function(x){
  analytemedians <- sapply(x[-1], median)
  median_of_median <- median(analytemedians)
  grand_median <- median(as.matrix(x[-1]))
  
  list(analytemedians = analytemedians,
       median_of_median = median_of_median,
       grand_median = grand_median)
}

mediansFunction(df)

#$analytemedians
#     2      3      4      5      7      8     10     12 
#55.960 56.505 56.410 56.320 56.510 56.323 56.500 56.355 

#$median_of_median
#[1] 56.3825

#$grand_median
#[1] 56.386