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DLAED3Run Method

Purpose ======= DLAED3 finds the roots of the secular equation, as defined by the values in D, W, and RHO, between 1 and K. It makes the appropriate calls to DLAED4 and then updates the eigenvectors by multiplying the matrix of eigenvectors of the pair of eigensystems being combined by the matrix of eigenvectors of the K-by-K system which is solved here. This code makes very mild assumptions about floating point arithmetic. It will work on machines with a guard digit in add/subtract, or on those binary machines without guard digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or Cray-2. It could conceivably fail on hexadecimal or decimal machines without guard digits, but we know of none.

Namespace: DotNumerics.LinearAlgebra.CSLapack
Assembly: DWSIM.MathOps.DotNumerics (in DWSIM.MathOps.DotNumerics.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
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public void Run(
	int K,
	int N,
	int N1,
	ref double[] D,
	int offset_d,
	ref double[] Q,
	int offset_q,
	int LDQ,
	double RHO,
	ref double[] DLAMDA,
	int offset_dlamda,
	double[] Q2,
	int offset_q2,
	int[] INDX,
	int offset_indx,
	int[] CTOT,
	int offset_ctot,
	ref double[] W,
	int offset_w,
	ref double[] S,
	int offset_s,
	ref int INFO
)
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Parameters

K  Int32
(input) INTEGER The number of terms in the rational function to be solved by DLAED4. K .GE. 0.
N  Int32
(input) INTEGER The number of rows and columns in the Q matrix. N .GE. K (deflation may result in N.GT.K).
N1  Int32
(input) INTEGER The location of the last eigenvalue in the leading submatrix. min(1,N) .LE. N1 .LE. N/2.
D  Double
(output) DOUBLE PRECISION array, dimension (N) D(I) contains the updated eigenvalues for 1 .LE. I .LE. K.
offset_d  Int32
 
Q  Double
(output) DOUBLE PRECISION array, dimension (LDQ,N) Initially the first K columns are used as workspace. On output the columns 1 to K contain the updated eigenvectors.
offset_q  Int32
 
LDQ  Int32
(input) INTEGER The leading dimension of the array Q. LDQ .GE. max(1,N).
RHO  Double
(input) DOUBLE PRECISION The value of the parameter in the rank one update equation. RHO .GE. 0 required.
DLAMDA  Double
(input/output) DOUBLE PRECISION array, dimension (K) The first K elements of this array contain the old roots of the deflated updating problem. These are the poles of the secular equation. May be changed on output by having lowest order bit set to zero on Cray X-MP, Cray Y-MP, Cray-2, or Cray C-90, as described above.
offset_dlamda  Int32
 
Q2  Double
(input) DOUBLE PRECISION array, dimension (LDQ2, N) The first K columns of this matrix contain the non-deflated eigenvectors for the split problem.
offset_q2  Int32
 
INDX  Int32
(input) INTEGER array, dimension (N) The permutation used to arrange the columns of the deflated Q matrix into three groups (see DLAED2). The rows of the eigenvectors found by DLAED4 must be likewise permuted before the matrix multiply can take place.
offset_indx  Int32
 
CTOT  Int32
(input) INTEGER array, dimension (4) A count of the total number of the various types of columns in Q, as described in INDX. The fourth column type is any column which has been deflated.
offset_ctot  Int32
 
W  Double
(input/output) DOUBLE PRECISION array, dimension (K) The first K elements of this array contain the components of the deflation-adjusted updating vector. Destroyed on output.
offset_w  Int32
 
S  Double
(workspace) DOUBLE PRECISION array, dimension (N1 + 1)*K Will contain the eigenvectors of the repaired matrix which will be multiplied by the previously accumulated eigenvectors to update the system.
offset_s  Int32
 
INFO  Int32
(output) INTEGER = 0: successful exit. .LT. 0: if INFO = -i, the i-th argument had an illegal value. .GT. 0: if INFO = 1, an eigenvalue did not converge
See Also