迭代R和商店列表中的列表

I have a list of matrix/vector and would like to apply R functions and store the output as a list in a sequence of numbers. As am example: I have a vector x and would like to calcualte min,max,median,quantile and store it in a list every iteration,

我有一个矩阵/向量列表，并希望应用R函数并将输出存储为数字序列中的列表。作为示例：我有一个向量x，并希望计算min，max，median，quantile并在每次迭代时将其存储在列表中，

outlist <- vector("list", 10)

for(p in seq(from=5, to=50, by=5))  {

  x <- c(rnorm(20)) 

  min <- min(x)
  max <- max(x)
  median <- median(x)
  quant <- quantile(x)

  outlist[[p]] <- list(c(min=min,max=max,median=median,quant=quant))

  print(p)
  }

The code above works fine, except that the output and has lots of "null" values . See below for the output from the program above, notice that 1 thru 4 is null and only in 5th iteration we start get the list output. This repeats for all the iteration. Can you please let me know how I should avoid null values in the output.

上面的代码工作正常，除了输出和有很多“null”值。请参阅下面有关上述程序的输出，请注意1到4为空，仅在第5次迭代中我们开始获取列表输出。这重复所有迭代。能告诉我如何避免输出中的空值。

Below are my questions. How to ensure all the null values are not present and only sequence numbers (p=5,10,15,...,50) in the iteration are present.

以下是我的问题。如何确保不存在所有空值，并且仅存在迭代中的序列号（p = 5,10,15，...，50）。

[[1]]
NULL

[[2]]
NULL

[[3]]
NULL

[[4]]
NULL

[[5]]
[[5]][[1]]
       min        max     median   quant.0%  quant.25%  quant.50%  quant.75% quant.100% 
-2.1058435  2.8461767 -0.5227028 -2.1058435 -1.1500056 -0.5227028  0.1645680  2.8461767

In addition, how to create a matrix(vector) output for list with row name as the sequence example ?

另外，如何为行列名作为序列示例创建列表的矩阵（向量）输出？

       min        max     median   quant.0%  quant.25%  quant.50%  quant.75% quant.100% 
5  -2.1058435  2.8461767 -0.5227028 -2.1058435 -1.1500056 -0.5227028  0.1645680  2.8461767 
10 -0.7709128  2.2872216  0.1808006 -0.7709128 -0.1501660  0.1808006  0.8250730  2.2872216 
15 -2.3748713  2.0360717  0.2638579 -2.3748713 -0.2631081  0.2638579  0.6446657  2.0360717

and so on ...

Thanks

谢谢

1 个解决方案

#1

You can build the list using the foreach package. The foreach function will return you a list and you can assign its names afterwards.

您可以使用foreach包构建列表。 foreach函数将返回一个列表，然后您可以指定其名称。

library(foreach)

vectorNames <- seq(from=5, to=50, by=5)

outlist <- foreach(p = vectorNames) %do% {

  x <- c(rnorm(20)) 

  min <- min(x)
  max <- max(x)
  median <- median(x)
  quant <- quantile(x)

  return(c(min=min,max=max,median=median,quant=quant))
}

names(outlist) <- vectorNames

Then, you can create the matrix using do.call and rbind.

然后，您可以使用do.call和rbind创建矩阵。

outmatrix <- do.call(rbind, outlist)
outmatrix

#1