ConstantArray {DelayedArray} | R Documentation

## A DelayedArray subclass that contains a constant value

### Description

A DelayedArray subclass to efficiently mimic an array containing a constant value, without actually creating said array in memory.

### Usage

    ## Constructor function:
    ConstantArray(dim, value=NA)

### Arguments

`dim` | The dimensions (specified as an integer vector) of the ConstantArray object to create.
`value` | Vector (atomic or list) of length 1, containing the value to fill the matrix.

### Details

This class allows us to efficiently create arrays containing a single value. For example, we can create matrices full of `NA` values, to serve as placeholders for missing assays when combining SummarizedExperiment objects.

### Value

A ConstantArray (or ConstantMatrix) object. (Note that ConstantMatrix extends ConstantArray.)

### Author(s)

Aaron Lun

### See Also

- DelayedArray objects.

- DelayedArray-utils for common operations on DelayedArray objects.

- RleArray objects for representing in-memory Run Length Encoded array-like datasets.

### Examples

    ## This would ordinarily take up 8 TB of memory:
    CM <- ConstantArray(c(1e6, 1e6), value=NA_real_)
    CM

    CM2 <-ConstantArray(c(4, 1e6), value=55)
    rbind(CM, CM2)

[Package DelayedArray version 0.20.0 Index]