expand {Matrix} | R Documentation

## Expand a Decomposition into Factors

### Description

Expands decompositions stored in compact form into factors.

### Usage

    expand(x, ...)

### Arguments

`x` | a matrix decomposition.
`...` | further arguments passed to or from other methods.

### Details

This is a generic function with special methods for different types of decompositions, see `showMethods(expand)` to list them all.

### Value

The expanded decomposition, typically a list of matrix factors.

### Note

Factors for decompositions such as `lu` and `qr` can be stored in a compact form. The function `expand` allows all factors to be fully expanded.

### See Also

The LU decomposition `lu`, for which there is an `expand` method; `facmul`.

### Examples

    (x <- Matrix(round(rnorm(9),2), 3, 3))
    (ex <- expand(lux <- lu(x)))

[Package Matrix version 1.0-6 Index]