按行而不是列用向量填充下矩阵 [英] Fill lower matrix with vector by row, not column

问题描述

我试图读取LISREL以下列格式在纯文本，空格分隔的文件中写出的方差-协方差矩阵:

I am trying to read in a variance-covariance matrix written out by LISREL in the following format in a plain text, whitespace separated file:

 0.23675E+01  0.86752E+00  0.28675E+01 -0.36190E+00 -0.36190E+00  0.25381E+01
-0.32571E+00 -0.32571E+00  0.84425E+00  0.25598E+01 -0.37680E+00 -0.37680E+00
 0.53136E+00  0.47822E+00  0.21120E+01 -0.37680E+00 -0.37680E+00  0.53136E+00
 0.47822E+00  0.91200E+00  0.21120E+01

这实际上是一个较低的对角矩阵(包括对角线):

This is actually a lower diagonal matrix (including diagonal):

 0.23675E+01  
 0.86752E+00  0.28675E+01 
-0.36190E+00 -0.36190E+00  0.25381E+01
-0.32571E+00 -0.32571E+00  0.84425E+00  0.25598E+01 
-0.37680E+00 -0.37680E+00  0.53136E+00  0.47822E+00  0.21120E+01 
-0.37680E+00 -0.37680E+00  0.53136E+00  0.47822E+00  0.91200E+00  0.21120E+01

我可以使用scan()或read.table(fill=T)正确读取值.

I can read in the values correctly with scan() or read.table(fill=T).

但是，我无法正确将读取的向量存储在矩阵中.以下代码

I am however not able to correctly store the read-in vector in a matrix. The following code

S <- diag(6)
S[lower.tri(S,diag=T)] <- d

按列填充下部矩阵，而应按行填充.

fills the lower matrix by column, while it should fill it by row.

使用matrix()确实允许使用选项byrow=TRUE，但这将填充整个矩阵，而不仅仅是下半部分(对角线).

Using matrix() does allow for the option byrow=TRUE, but this will fill in the whole matrix, not just the lower half (with diagonal).

是否可以同时使用这两种方法:仅填充较低的矩阵(对角线)，并且按行执行?

Is it possible to have both: only fill the lower matrix (with diagonal) and do it by row?

(我遇到的另一个问题:LISREL使用'D + 01'，而R仅将'E + 01'表示为科学计数法.您可以在R中将其更改为也接受'D'吗?)

(separate issue I'm having: LISREL uses 'D+01' while R only recognises 'E+01' for scientific notation. Can you change this in R to accept also 'D'?)

推荐答案

只需将其读入上方的三角形部分，而不是下方的部分:

Just read it into the upper triangular portion, rather than the lower:

S <- diag(6)
S[upper.tri(S, diag=TRUE)] <- d
t(S)

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