Fac_Cholesky

scalation.mathstat.Fac_Cholesky
class Fac_Cholesky(a: MatrixD) extends Factorization

The Fac_Cholesky class provides methods to factor an n-by-n symmetric, positive definite matrix a into the product of two matrices: l - an n-by-n left lower triangular matrix l.t - an n-by-n right upper triangular matrix - transpose of l such that a = l * l.t.

Value parameters

a

the symmetric, positive definite matrix to be factor

Attributes

Graph
Supertypes
class Object
trait Matchable
class Any

Members list

Value members

Concrete methods

Factor matrix a into the product of l and l.t using Cholesky Factorization a = l * l.t, where l.t is l's transpose. It uses the Cholesky–Banachiewicz algorithm.

Factor matrix a into the product of l and l.t using Cholesky Factorization a = l * l.t, where l.t is l's transpose. It uses the Cholesky–Banachiewicz algorithm.

Attributes

See also

introcs.cs.princeton.edu/java/95linear

Factor matrix a into the product of l and l.t using Cholesky Factorization a = l * l.t, where l.t is l's transpose. This is a more robust Cholesky Factorization algorithm. Adpated from Scala 2 code returned by GPT-3 on the query: "more robust Cholesky Factorization algorithm in Scala" Also #see math.stackexchange.com/questions/418945/cholesky-decomposition-in-positive-semi-definite-matrix

Factor matrix a into the product of l and l.t using Cholesky Factorization a = l * l.t, where l.t is l's transpose. This is a more robust Cholesky Factorization algorithm. Adpated from Scala 2 code returned by GPT-3 on the query: "more robust Cholesky Factorization algorithm in Scala" Also #see math.stackexchange.com/questions/418945/cholesky-decomposition-in-positive-semi-definite-matrix

Attributes

Factor matrix a into the product of l and l.t using Cholesky Factorization a = l * l.t, where l.t is l's transpose. It uses the Cholesky–Crout algorithm.

Factor matrix a into the product of l and l.t using Cholesky Factorization a = l * l.t, where l.t is l's transpose. It uses the Cholesky–Crout algorithm.

Attributes

Return both the lower triangular matrix l and its transpose l.t.

Return both the lower triangular matrix l and its transpose l.t.

Attributes

Efficient calculation of inverse matrix a^-1 from existing factorization. a * a^-1 = I

Efficient calculation of inverse matrix a^-1 from existing factorization. a * a^-1 = I

Attributes

def solve(b: VectorD): VectorD

Use the lower triangular matrix l from the Cholesky Factorization to solve a system of equations a * x = b. Return the solution x using forward and backward substitution.

Use the lower triangular matrix l from the Cholesky Factorization to solve a system of equations a * x = b. Return the solution x using forward and backward substitution.

Value parameters

b

the constant vector

Attributes

Inherited methods

def factor1(): MatrixD

Factor a matrix into the product of two matrices, e.g., 'a = l * l.t', returning only the first matrix.

Factor a matrix into the product of two matrices, e.g., 'a = l * l.t', returning only the first matrix.

Attributes

Inherited from:
Factorization

Factor a matrix into the product of two matrices, e.g., 'a = l * l.t' or a = q * r, returning both the first and second matrices.

Factor a matrix into the product of two matrices, e.g., 'a = l * l.t' or a = q * r, returning both the first and second matrices.

Attributes

Inherited from:
Factorization
def factor2(): MatrixD

Factor a matrix into the product of two matrices, e.g., 'a = l * l.t', returning only the second matrix.

Factor a matrix into the product of two matrices, e.g., 'a = l * l.t', returning only the second matrix.

Attributes

Inherited from:
Factorization
inline def isFactored: Boolean

Return whether the matrix has been factored has aleady been factored.

Return whether the matrix has been factored has aleady been factored.

Attributes

Inherited from:
Factorization
def reset(): Unit

Reset by setting factored to false.

Reset by setting factored to false.

Attributes

Inherited from:
Factorization

Inherited fields

protected var factored: Boolean

Flag indicating whether the matrix has been factored

Flag indicating whether the matrix has been factored

Attributes

Inherited from:
Factorization