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DLARZTRun Method

Purpose ======= DLARZT forms the triangular factor T of a real block reflector H of order .GT. n, which is defined as a product of k elementary reflectors. If DIRECT = 'F', H = H(1) H(2) . . . H(k) and T is upper triangular; If DIRECT = 'B', H = H(k) . . . H(2) H(1) and T is lower triangular. If STOREV = 'C', the vector which defines the elementary reflector H(i) is stored in the i-th column of the array V, and H = I - V * T * V' If STOREV = 'R', the vector which defines the elementary reflector H(i) is stored in the i-th row of the array V, and H = I - V' * T * V Currently, only STOREV = 'R' and DIRECT = 'B' are supported.

Namespace: DotNumerics.LinearAlgebra.CSLapack
Assembly: DWSIM.MathOps.DotNumerics (in DWSIM.MathOps.DotNumerics.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
Copy
public void Run(
	string DIRECT,
	string STOREV,
	int N,
	int K,
	double[] V,
	int offset_v,
	int LDV,
	double[] TAU,
	int offset_tau,
	ref double[] T,
	int offset_t,
	int LDT
)
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Parameters

DIRECT  String
(input) CHARACTER*1 Specifies the order in which the elementary reflectors are multiplied to form the block reflector: = 'F': H = H(1) H(2) . . . H(k) (Forward, not supported yet) = 'B': H = H(k) . . . H(2) H(1) (Backward)
STOREV  String
(input) CHARACTER*1 Specifies how the vectors which define the elementary reflectors are stored (see also Further Details): = 'C': columnwise (not supported yet) = 'R': rowwise
N  Int32
(input) INTEGER The order of the block reflector H. N .GE. 0.
K  Int32
(input) INTEGER The order of the triangular factor T (= the number of elementary reflectors). K .GE. 1.
V  Double
(input/output) DOUBLE PRECISION array, dimension (LDV,K) if STOREV = 'C' (LDV,N) if STOREV = 'R' The matrix V. See further details.
offset_v  Int32
 
LDV  Int32
(input) INTEGER The leading dimension of the array V. If STOREV = 'C', LDV .GE. max(1,N); if STOREV = 'R', LDV .GE. K.
TAU  Double
(input) DOUBLE PRECISION array, dimension (K) TAU(i) must contain the scalar factor of the elementary reflector H(i).
offset_tau  Int32
 
T  Double
(output) DOUBLE PRECISION array, dimension (LDT,K) The k by k triangular factor T of the block reflector. If DIRECT = 'F', T is upper triangular; if DIRECT = 'B', T is lower triangular. The rest of the array is not used.
offset_t  Int32
 
LDT  Int32
(input) INTEGER The leading dimension of the array T. LDT .GE. K.
See Also