1_subsetting_operators: Subsetting Operators

Description Usage Arguments Details Examples

Description

Subsetting operators for vector-like objects.

Usage

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## S3 method for class 'ObjectArray'
x[[...]]
## S3 replacement method for class 'ObjectArray'
x[[...]] <- value

## S3 method for class 'NestMatrix'
x[[i, j]]
## S3 replacement method for class 'NestMatrix'
x[[i, j]] <- value

## S3 method for class 'SectMatrix'
x[...]
## S3 replacement method for class 'SectMatrix'
x[...] <- value
## S3 method for class 'SectMatrix'
x[[i, j]]
## S3 replacement method for class 'SectMatrix'
x[[i, j]] <- value

Arguments

x

A vector-like object.

i, j, ...

The indices.

value

The value to assign. For SectMatrix, the dimensions of the value need to match the dimensions set by setmap.

Details

ObjectArray and NestMatrix, are similar to lists, so:
Double bracket subsetting gets or sets a single element.

For SectMatrix (including PartMatrix):
Single bracket subsetting indexes submatrices and double bracket subsetting indexes the combined matrix.

Note that this may be changed in the future.

Examples

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s = matrix (1:16, 4, 4)

#2x2 nested matrix, with 4 2x2 submatrices
x = as.NestMatrix (s, 2, 2)
x

x [[1, 1]]       #2x2 matrix
x [[1, 1]][2, 2] #6

#4x4 nested matrix, with 16 scalar values
x = as.NestMatrix.2 (s)
x

x [[2, 2]]       #6

#4x4 partitioned matrix, partitioned into 4 2x2 submatrices
x = as.PartMatrix (s, 2, 2)
x

x [1, 1]        #2x2 matrix
x [[2, 2]]      #6
x [1, 1][2, 2]  #6

vectools documentation built on Jan. 9, 2020, 5:09 p.m.