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Function dlaed2_

numpy/linalg/lapack_lite/f2c_d_lapack.c:9352–9862  ·  view source on GitHub ↗

Subroutine */

Source from the content-addressed store, hash-verified

9350} /* dlaed1_ */
9351
9352/* Subroutine */ int dlaed2_(integer *k, integer *n, integer *n1, doublereal *
9353 d__, doublereal *q, integer *ldq, integer *indxq, doublereal *rho,
9354 doublereal *z__, doublereal *dlamda, doublereal *w, doublereal *q2,
9355 integer *indx, integer *indxc, integer *indxp, integer *coltyp,
9356 integer *info)
9357{
9358 /* System generated locals */
9359 integer q_dim1, q_offset, i__1, i__2;
9360 doublereal d__1, d__2, d__3, d__4;
9361
9362 /* Local variables */
9363 static doublereal c__;
9364 static integer i__, j;
9365 static doublereal s, t;
9366 static integer k2, n2, ct, nj, pj, js, iq1, iq2, n1p1;
9367 static doublereal eps, tau, tol;
9368 static integer psm[4], imax, jmax;
9369 extern /* Subroutine */ int drot_(integer *, doublereal *, integer *,
9370 doublereal *, integer *, doublereal *, doublereal *);
9371 static integer ctot[4];
9372 extern /* Subroutine */ int dscal_(integer *, doublereal *, doublereal *,
9373 integer *), dcopy_(integer *, doublereal *, integer *, doublereal
9374 *, integer *);
9375
9376 extern integer idamax_(integer *, doublereal *, integer *);
9377 extern /* Subroutine */ int dlamrg_(integer *, integer *, doublereal *,
9378 integer *, integer *, integer *), dlacpy_(char *, integer *,
9379 integer *, doublereal *, integer *, doublereal *, integer *), xerbla_(char *, integer *);
9380
9381
9382/*
9383 -- LAPACK routine (version 3.2) --
9384 -- LAPACK is a software package provided by Univ. of Tennessee, --
9385 -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
9386 November 2006
9387
9388
9389 Purpose
9390 =======
9391
9392 DLAED2 merges the two sets of eigenvalues together into a single
9393 sorted set. Then it tries to deflate the size of the problem.
9394 There are two ways in which deflation can occur: when two or more
9395 eigenvalues are close together or if there is a tiny entry in the
9396 Z vector. For each such occurrence the order of the related secular
9397 equation problem is reduced by one.
9398
9399 Arguments
9400 =========
9401
9402 K (output) INTEGER
9403 The number of non-deflated eigenvalues, and the order of the
9404 related secular equation. 0 <= K <=N.
9405
9406 N (input) INTEGER
9407 The dimension of the symmetric tridiagonal matrix. N >= 0.
9408
9409 N1 (input) INTEGER

Callers 1

dlaed1_Function · 0.85

Calls 11

dscal_Function · 0.85
absFunction · 0.85
dlamrg_Function · 0.85
idamax_Function · 0.85
dcopy_Function · 0.85
dlacpy_Function · 0.85
dlapy2_Function · 0.85
drot_Function · 0.85
maxFunction · 0.50
minFunction · 0.50
sqrtFunction · 0.50

Tested by

no test coverage detected