matrix_to_blocks.RdSplit a matrix into a list of blocks (either by rows or by columns)
matrix_to_blocks(Matrix, blocks, byrow = TRUE)a matrix to split
either a list or a vector indicating the
blocks. If blocks is a list of vectors, then the
length of each vector defines the size of the blocks. If
blocks is a vector, then each element represents
the size of the blocks.
logical. If TRUE (the default) the
matrix is split by rows, otherwise the matrix is split by
columns
A list of matrices
# matrix with 10 rows and 7 columns
M = matrix(rnorm(70), 10, 7)
# row blocks
row_sets = list(1:3, 4:5, 6:10)
# split matrix by rows
matrix_to_blocks(M, row_sets)
#> [[1]]
#> [,1] [,2] [,3] [,4] [,5] [,6]
#> [1,] -1.333516 1.0229750 -0.1389818 -0.3318437 -0.3664693 0.3312638
#> [2,] 1.740138 -1.6911442 2.7308061 -0.9159330 -0.7477748 0.4303582
#> [3,] 3.676596 -0.5893431 0.6826662 0.5437173 -1.7425781 -0.6301231
#> [,7]
#> [1,] -1.2201014
#> [2,] 0.2358788
#> [3,] -1.1874375
#>
#> [[2]]
#> [,1] [,2] [,3] [,4] [,5] [,6]
#> [1,] 0.7250420 -0.0005062043 0.27905441 -1.065672 -1.109569 2.0205857
#> [2,] 0.1450109 -0.7360230462 0.01487457 -1.514387 1.113836 -0.9881449
#> [,7]
#> [1,] -0.09779199
#> [2,] -1.58698737
#>
#> [[3]]
#> [,1] [,2] [,3] [,4] [,5] [,6]
#> [1,] -0.293653448 0.994442832 0.4571903 -0.3947118 1.8990917 -0.2887112
#> [2,] 0.600989971 -0.251166858 -0.9046805 -0.4737186 -0.6608972 1.9126630
#> [3,] 0.664280586 -0.710994405 -0.3068376 -1.5053322 -1.8589667 -1.7442175
#> [4,] 0.004414104 0.182786220 -1.0879656 -1.7395430 -0.6630963 -0.7551556
#> [5,] 0.082652589 0.008086858 1.4535832 -1.1587191 1.3037711 0.4954030
#> [,7]
#> [1,] -0.6539435
#> [2,] -0.3245454
#> [3,] -0.6911203
#> [4,] -0.4474582
#> [5,] -0.3598401
#>
# column blocks
col_sets = c(3, 4)
# split matrix by rows
matrix_to_blocks(M, col_sets, byrow=FALSE)
#> [[1]]
#> [,1] [,2] [,3]
#> [1,] -1.333515545 1.0229749642 -0.13898176
#> [2,] 1.740137930 -1.6911442196 2.73080611
#> [3,] 3.676595856 -0.5893431235 0.68266615
#> [4,] 0.725042032 -0.0005062043 0.27905441
#> [5,] 0.145010856 -0.7360230462 0.01487457
#> [6,] -0.293653448 0.9944428321 0.45719028
#> [7,] 0.600989971 -0.2511668577 -0.90468052
#> [8,] 0.664280586 -0.7109944054 -0.30683755
#> [9,] 0.004414104 0.1827862198 -1.08796561
#> [10,] 0.082652589 0.0080868584 1.45358320
#>
#> [[2]]
#> [,1] [,2] [,3] [,4]
#> [1,] -0.3318437 -0.3664693 0.3312638 -1.22010144
#> [2,] -0.9159330 -0.7477748 0.4303582 0.23587883
#> [3,] 0.5437173 -1.7425781 -0.6301231 -1.18743753
#> [4,] -1.0656719 -1.1095688 2.0205857 -0.09779199
#> [5,] -1.5143872 1.1138355 -0.9881449 -1.58698737
#> [6,] -0.3947118 1.8990917 -0.2887112 -0.65394346
#> [7,] -0.4737186 -0.6608972 1.9126630 -0.32454538
#> [8,] -1.5053322 -1.8589667 -1.7442175 -0.69112030
#> [9,] -1.7395430 -0.6630963 -0.7551556 -0.44745820
#> [10,] -1.1587191 1.3037711 0.4954030 -0.35984012
#>