当矩阵的维度未知时，如何设置矩阵的唯一行和列名称? [英] How to set unique row and column names of a matrix when its dimension is unknown?

问题描述

我有这样的矩阵:

     [,1][,2][,3][,4]
[1,]  12  32  43  55
[2,]  54  54  7   8
[3,]  2   56  76  88
[4,]  58  99  93  34

我事先不知道矩阵中有多少行和列.因此，我需要动态创建行名和列名.

I do not know in advance how many rows and columns I will have in matrix. Thus, I need to create row and column names dynamically.

我可以直接命名列(行)，例如:

I can name columns (row) directly like:

colnames(rmatrix) <- c("a", "b", "c", "d")

但是，如何动态创建名称向量以适应矩阵的维度?

However, how can I create my names vector dynamically to fit the dimensions of the matrix?

nm <- ("a", "b", "c", "d")
colnames(rmatrix) <- nm 

推荐答案

您可以使用 rownames 和 colnames 并设置 do.NULL=FALSE 为了动态创建名称，如:

You can use rownames and colnames and setting do.NULL=FALSE in order to create names dynamically, as in:

set.seed(1)
rmatrix  <-  matrix(sample(0:100, 16), ncol=4)

dimnames(rmatrix) <- list(rownames(rmatrix, do.NULL = FALSE, prefix = "row"),
                          colnames(rmatrix, do.NULL = FALSE, prefix = "col"))

rmatrix
     col1 col2 col3 col4
row1   26   19   58   61
row2   37   86    5   33
row3   56   97   18   66
row4   89   62   15   42

您可以更改 prefix 以根据需要命名行/列.

you can change prefix to name the rows/cols as you want to.

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