Decomposition Operations<TReal, TComplex>.Triangular Estimate Condition Method
Definition
Namespace: Extreme.Mathematics.LinearAlgebra.Implementation
Assembly: Extreme.Numerics (in Extreme.Numerics.dll) Version: 8.1.23
Assembly: Extreme.Numerics (in Extreme.Numerics.dll) Version: 8.1.23
Overload List
Triangular | Estimates the reciprocal of the condition number of a triangular matrix A, in either the 1-norm or the infinity-norm. |
Triangular | Approximates the reciprocal of the condition number of a complex triangular matrix. |
TriangularEstimateCondition(MatrixNorm, MatrixTriangle, MatrixDiagonal, Int32, Array2D<TReal>, TReal, Int32)
Estimates the reciprocal of the condition number of a triangular matrix A, in either the 1-norm or the infinity-norm.
public abstract void TriangularEstimateCondition(
MatrixNorm norm,
MatrixTriangle storedTriangle,
MatrixDiagonal diag,
int n,
Array2D<TReal> a,
out TReal rcond,
out int info
)
Parameters
- norm MatrixNorm
Specifies whether the 1-norm condition number or the infinity-norm condition number is required: = '1' or 'O': 1-norm; = 'I': Infinity-norm.
- storedTriangle MatrixTriangle
= 'U': A is upper triangular; = 'L': A is lower triangular.
- diag MatrixDiagonal
= 'N': A is non-unit triangular; = 'U': A is unit triangular.
- n Int32
The order of the matrix A. N >= 0.
- a Array2D<TReal>
A is TReal array, dimension (LDA,N) The triangular matrix A. If UPLO = 'U', the leading N-by-N upper triangular part of the array A contains the upper triangular matrix, and the strictly lower triangular part of A is not referenced. If UPLO = 'L', the leading N-by-N lower triangular part of the array A contains the lower triangular matrix, and the strictly upper triangular part of A is not referenced. If DIAG = 'U', the diagonal elements of A are also not referenced and are assumed to be 1.
The leading dimension of the array A. LDA >= max(1,N).
- rcond TReal
RCOND is TReal The reciprocal of the condition number of the matrix A, computed as RCOND = 1/(norm(A) * norm(inv(A))).
- info Int32
= 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value
Remarks
The norm of A is computed and an estimate is obtained for norm(inv(A)), then the reciprocal of the condition number is computed as RCOND = 1 / ( norm(A) * norm(inv(A)) ).
This method corresponds to the LAPACK routine ?TRCON.
TriangularEstimateCondition(MatrixNorm, MatrixTriangle, MatrixDiagonal, Int32, Array2D<TComplex>, TReal, Int32)
Approximates the reciprocal of the condition number of a complex triangular matrix.
public abstract void TriangularEstimateCondition(
MatrixNorm norm,
MatrixTriangle storedTriangle,
MatrixDiagonal diag,
int n,
Array2D<TComplex> a,
out TReal rcond,
out int info
)
Parameters
- norm MatrixNorm
- A MatrixNorm value that specifies which norm to use in the expression for the condition number.
- storedTriangle MatrixTriangle
- A MatrixTriangle value that indicates whether the matrix is upper or lower triangular.
- diag MatrixDiagonal
- A MatrixDiagonal value that indicates whether the matrix is unit diagonal.
- n Int32
- The number of rows and columns of the matrix.
- a Array2D<TComplex>
- A complex array that contains the elements of the matrix.
- rcond TReal
- On return, an estimate for the reciprocal of the condition number of the matrix.
- info Int32
- On return, indicates error conditions.