matrixset (version 0.4.0)

[<-.matrixset: Replace Parts of a matrixset

Description

Replace whole or parts of some - or all - matrices of a matrixset.

Usage

# S3 method for matrixset
[(x, i = NULL, j = NULL, matrix = NULL) <- value

Value

A matrixset, with proper elements replaced.

Arguments

x

matrixset object from which to replace element(s)

i, j

Indices specifying elements to replace. Indices are numeric or character vectors or empty (NULL). Note that treating NULL as empty differs from the usual replacement, where it is treated as integer(0). Here a NULL (empty) results in selecting all rows or columns.

Numeric values are coerced to integer as by [as.integer()] (and hence
truncated towards zero).

Character vectors will be matched to the dimnames of the object.

Can also be logical vectors, indicating elements/slices to replace Such vectors are **NOT** recycled, which is an important difference with usual matrix replacement. It means that the logical vector must match the object dimension in length.

Can also be negative integers, indicating elements/slices to leave out of the replacement.

When indexing, a single argument `i` can be a matrix with two columns. This is treated as if the first column was the `i` index and the second column the `j` index.

matrix

index specifying matrix or matrices to replace. Index is numeric or character vectors or empty (NULL). Note that treating NULL as empty differs from the usual replacement, where it is treated as integer(0). Here a NULL (empty) results in replacing all matrices.

Numeric values are coerced to integer as by as.integer() (and hence truncated towards zero).

Character vectors will be matched to the matrix names of the object.

Can also be logical vectors, indicating elements/slices to replace. Such vectors are NOT recycled, which is an important difference with usual matrix replacement. It means that the logical vector must match the number of matrices in length.

Can also be negative integers, indicating elements/slices to leave out of the replacement.

value

object to use as replacement value

vector <code>value</code>

Contrarily to matrix replacement, when submitting an atomic vector value, dimensions must match exactly.

Replacing <code>NULL</code> matrices

Replacing subscripts of NULL matrices is not possible, unless value is itself NULL, or a matrix the same dimensions (number of rows and columns) as x. If x has dimnames, value must have the same dimnames.

Details

If matrix is left unspecified (or given as NULL), all matrices will be replaced by value. How replacement exactly occurs depends on value itself.

If value is a single atomic vector (this excludes lists) or matrix, relevant subscripts of all requested matrices will be replaced by the same value. This is conditional to the dimensions being compatible.

Alternatively, value can be a list of atomic vectors/matrices. If value has a single element, the same rules as above apply. Otherwise, the length of value must match the number of matrices for which subscripts have to be replaced.

If the list elements are named, the names are matched to the names of the matrices that need replacement - in which case value needs not to be the same length.

A final possibility for value is for it to be NULL. In this case, target matrices are turned to NULL.

Examples

# an hypothetical example of students that failed 3 courses and their results
# after remedial class

# you can replace a line for all matrices at once. In the example, the "wrong"
# tag refers to the fact that the 'failure' results do not make sense after
# replacement
student_results_wrong <- student_results
student_results_wrong["student 2",,] <- c(0.81, 0.88, 0.71) # obviously, integer index works too
# note how all matrices had the same replacement
student_results_wrong

# this already makes more sense in the context of the example
student_results[2,,] <- list(c(0,0.45,0.1), c(0.81, 0.88, 0.71))
student_results

# or even these two equivalent commands
student_results["student 2",,"remedial"] <- c(0.77, 0.83, 0.75)
student_results[2,,2] <- matrix(c(0.77, 0.83, 0.75), 1, 3)