matrix_to_blocks: Split a matrix into blocks

In turner: Turn vectors and lists of vectors into indexed structures

Description

Split a matrix into a list of blocks (either by rows or by columns)

Usage

  matrix_to_blocks(Matrix, blocks, byrow = TRUE)

Arguments

Matrix	a matrix to split
blocks	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.
byrow	logical. If TRUE (the default) the matrix is split by rows, otherwise the matrix is split by columns

Value

A list of matrices

Author(s)

Gaston Sanchez

See Also

lengths, listsize

Examples

# 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)

# column blocks
col_sets = c(3, 4)

# split matrix by rows
matrix_to_blocks(M, col_sets, byrow=FALSE)

Example output

Attaching package: 'turner'

The following object is masked from 'package:base':

    lengths

[[1]]
           [,1]       [,2]      [,3]      [,4]       [,5]      [,6]       [,7]
[1,] -0.5472893 -0.5902474 0.2471662 1.4983757 -0.6286968  1.685142  1.9044569
[2,]  0.2726798 -0.6452849 1.1895195 0.5676669 -1.0244267 -2.112856 -0.3411200
[3,] -0.1496725  1.2772919 2.0255955 1.3402460 -0.5257598  1.780134  0.3090321

[[2]]
           [,1]       [,2]     [,3]       [,4]      [,5]       [,6]       [,7]
[1,] -0.2777342 -0.9177540 1.721689  0.4761462 0.6535606 -0.5722103  1.4749489
[2,] -0.5424928 -0.3411447 1.246191 -1.1016969 0.1227002  0.7753965 -0.5576772

[[3]]
           [,1]       [,2]       [,3]       [,4]       [,5]       [,6]
[1,] -1.7790559 -0.7345397 -0.3675565 -0.8344598  1.7496380 -1.9401020
[2,]  2.1104226 -0.5628160 -0.4601471  0.8364645 -0.1854451 -0.2970309
[3,]  0.8395387  0.4903054  1.7758980 -1.4065472 -0.8955588  0.3294168
[4,] -0.8539439 -0.6033897 -0.6575203  0.7529293  1.0040618  1.0985585
[5,] -1.0910718 -1.2841380 -1.2995096  1.0075262 -0.0390433  0.4508892
             [,7]
[1,] -0.913232638
[2,]  0.641387028
[3,] -0.048036141
[4,] -0.009841404
[5,] -0.042836974

[[1]]
            [,1]       [,2]       [,3]
 [1,] -0.5472893 -0.5902474  0.2471662
 [2,]  0.2726798 -0.6452849  1.1895195
 [3,] -0.1496725  1.2772919  2.0255955
 [4,] -0.2777342 -0.9177540  1.7216887
 [5,] -0.5424928 -0.3411447  1.2461906
 [6,] -1.7790559 -0.7345397 -0.3675565
 [7,]  2.1104226 -0.5628160 -0.4601471
 [8,]  0.8395387  0.4903054  1.7758980
 [9,] -0.8539439 -0.6033897 -0.6575203
[10,] -1.0910718 -1.2841380 -1.2995096

[[2]]
            [,1]       [,2]       [,3]         [,4]
 [1,]  1.4983757 -0.6286968  1.6851420  1.904456937
 [2,]  0.5676669 -1.0244267 -2.1128559 -0.341120014
 [3,]  1.3402460 -0.5257598  1.7801340  0.309032087
 [4,]  0.4761462  0.6535606 -0.5722103  1.474948948
 [5,] -1.1016969  0.1227002  0.7753965 -0.557677250
 [6,] -0.8344598  1.7496380 -1.9401020 -0.913232638
 [7,]  0.8364645 -0.1854451 -0.2970309  0.641387028
 [8,] -1.4065472 -0.8955588  0.3294168 -0.048036141
 [9,]  0.7529293  1.0040618  1.0985585 -0.009841404
[10,]  1.0075262 -0.0390433  0.4508892 -0.042836974

turner documentation built on May 2, 2019, 8:35 a.m.