如果我有一个相同维度的矩阵列表,如何在 R 中获取矩阵列表的每个元素?例如,我有 4 个矩阵:
> a
[,1] [,2] [,3]
[1,] -0.8761453 0.2821336 -0.8541406
[2,] -0.9649200 1.7734091 -1.2058440
[3,] -0.4250063 -0.8197162 -1.3997540
> b
[,1] [,2] [,3]
[1,] -1.2096577 -0.5440074 0.6102016
[2,] -0.1299645 -0.8943189 -1.8042720
[3,] 1.0111488 0.2547343 0.2395172
> c
[,1] [,2] [,3]
[1,] 0.2853833 -0.2716714 0.2330467
[2,] -0.7963095 -1.2120779 0.6909755
[3,] 0.3479346 0.1803124 -0.7400176
> d
[,1] [,2] [,3]
[1,] -1.048740842 -1.0492152 -0.6889409
[2,] -0.004154795 -0.6167335 -0.8028550
[3,] -1.111915258 -2.1586534 -0.1448612
我想要的结果是,如果我想要每个元素的第二个最小值。
> res
[,1] [,2] [,3]
[1,] -1.0487408 -0.5440074 -0.6889409
[2,] -0.7963095 -0.8943189 -1.2058440
[3,] -0.4250063 -0.8197162 -0.7400176
如果我们需要第二个最小值,通过将matrix
es 连接在一起来创建array
,指定维度并使用具有所需MARGIN
的apply
,将元素从小到大sort
并得到第二个元素
apply(array(c(a, b, c, d), c(dim(a), 4)), c(1, 2), FUN = function(x) sort(x)[2])
# [,1] [,2] [,3]
#[1,] -1.0487408 -0.5440074 -0.6889409
#[2,] -0.7963095 -0.8943189 -1.2058440
#[3,] -0.4250063 -0.8197162 -0.7400176
注意:根据OP的帖子,看起来"a","b","c","d"是全局环境中matrix
单独的对象