Subroutine */
| 38509 | } /* dsteqr_ */ |
| 38510 | |
| 38511 | /* Subroutine */ int dsterf_(integer *n, doublereal *d__, doublereal *e, |
| 38512 | integer *info) |
| 38513 | { |
| 38514 | /* System generated locals */ |
| 38515 | integer i__1; |
| 38516 | doublereal d__1, d__2, d__3; |
| 38517 | |
| 38518 | /* Local variables */ |
| 38519 | static doublereal c__; |
| 38520 | static integer i__, l, m; |
| 38521 | static doublereal p, r__, s; |
| 38522 | static integer l1; |
| 38523 | static doublereal bb, rt1, rt2, eps, rte; |
| 38524 | static integer lsv; |
| 38525 | static doublereal eps2, oldc; |
| 38526 | static integer lend, jtot; |
| 38527 | extern /* Subroutine */ int dlae2_(doublereal *, doublereal *, doublereal |
| 38528 | *, doublereal *, doublereal *); |
| 38529 | static doublereal gamma, alpha, sigma, anorm; |
| 38530 | |
| 38531 | static integer iscale; |
| 38532 | extern /* Subroutine */ int dlascl_(char *, integer *, integer *, |
| 38533 | doublereal *, doublereal *, integer *, integer *, doublereal *, |
| 38534 | integer *, integer *); |
| 38535 | static doublereal oldgam, safmin; |
| 38536 | extern /* Subroutine */ int xerbla_(char *, integer *); |
| 38537 | static doublereal safmax; |
| 38538 | extern doublereal dlanst_(char *, integer *, doublereal *, doublereal *); |
| 38539 | extern /* Subroutine */ int dlasrt_(char *, integer *, doublereal *, |
| 38540 | integer *); |
| 38541 | static integer lendsv; |
| 38542 | static doublereal ssfmin; |
| 38543 | static integer nmaxit; |
| 38544 | static doublereal ssfmax; |
| 38545 | |
| 38546 | |
| 38547 | /* |
| 38548 | -- LAPACK routine (version 3.2) -- |
| 38549 | -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 38550 | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 38551 | November 2006 |
| 38552 | |
| 38553 | |
| 38554 | Purpose |
| 38555 | ======= |
| 38556 | |
| 38557 | DSTERF computes all eigenvalues of a symmetric tridiagonal matrix |
| 38558 | using the Pal-Walker-Kahan variant of the QL or QR algorithm. |
| 38559 | |
| 38560 | Arguments |
| 38561 | ========= |
| 38562 | |
| 38563 | N (input) INTEGER |
| 38564 | The order of the matrix. N >= 0. |
| 38565 | |
| 38566 | D (input/output) DOUBLE PRECISION array, dimension (N) |
| 38567 | On entry, the n diagonal elements of the tridiagonal matrix. |
| 38568 | On exit, if INFO = 0, the eigenvalues in ascending order. |