IsInvertible: Test for an Invertible Matrix

In jeksterslab/matrixR: Matrix/Linear Algebra

Description

IsInvertible() returns TRUE if A is an invertible matrix, and FALSE otherwise.

Usage

IsInvertible(A, tol = 1e-08)

Arguments

A	Input.
tol	Numeric. Tolerance.

Details

An m \times m matrix \mathbf{A} is invertible if there exists an m \times m matrix \mathbf{B} such that

\mathbf{A} \mathbf{B} = \mathbf{B} \mathbf{A} = \mathbf{I}_{m}

where \mathbf{I}_{m} is an m \times m identity matrix.

An m \times m matrix \mathbf{A} is noninvertible or singular if its determinant is zero.

A is considered invertible if its determinant is NOT less than or equal to a tolerance value.

Value

Logical.

Author(s)

Ivan Jacob Agaloos Pesigan

See Also

Other predicate functions: IsDiagonal(), IsIdempotent(), IsMatrix(), IsNilpotent(), IsOrthogonal(), IsPositiveDefinite(), IsScalar(), IsSingular(), IsSquareMatrix(), IsSymmetric(), IsVector(), MatrixCheck()

Examples

# TRUE
IsInvertible(diag(2))

# FALSE
IsInvertible(matrix(1, nrow = 2, ncol = 2))

jeksterslab/matrixR documentation built on Feb. 22, 2021, 8:10 a.m.