Subroutine */
| 9862 | } /* dlaed2_ */ |
| 9863 | |
| 9864 | /* Subroutine */ int dlaed3_(integer *k, integer *n, integer *n1, doublereal * |
| 9865 | d__, doublereal *q, integer *ldq, doublereal *rho, doublereal *dlamda, |
| 9866 | doublereal *q2, integer *indx, integer *ctot, doublereal *w, |
| 9867 | doublereal *s, integer *info) |
| 9868 | { |
| 9869 | /* System generated locals */ |
| 9870 | integer q_dim1, q_offset, i__1, i__2; |
| 9871 | doublereal d__1; |
| 9872 | |
| 9873 | /* Local variables */ |
| 9874 | static integer i__, j, n2, n12, ii, n23, iq2; |
| 9875 | static doublereal temp; |
| 9876 | extern doublereal dnrm2_(integer *, doublereal *, integer *); |
| 9877 | extern /* Subroutine */ int dgemm_(char *, char *, integer *, integer *, |
| 9878 | integer *, doublereal *, doublereal *, integer *, doublereal *, |
| 9879 | integer *, doublereal *, doublereal *, integer *), |
| 9880 | dcopy_(integer *, doublereal *, integer *, doublereal *, integer |
| 9881 | *), dlaed4_(integer *, integer *, doublereal *, doublereal *, |
| 9882 | doublereal *, doublereal *, doublereal *, integer *); |
| 9883 | extern doublereal dlamc3_(doublereal *, doublereal *); |
| 9884 | extern /* Subroutine */ int dlacpy_(char *, integer *, integer *, |
| 9885 | doublereal *, integer *, doublereal *, integer *), |
| 9886 | dlaset_(char *, integer *, integer *, doublereal *, doublereal *, |
| 9887 | doublereal *, integer *), xerbla_(char *, integer *); |
| 9888 | |
| 9889 | |
| 9890 | /* |
| 9891 | -- LAPACK routine (version 3.2) -- |
| 9892 | -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 9893 | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 9894 | November 2006 |
| 9895 | |
| 9896 | |
| 9897 | Purpose |
| 9898 | ======= |
| 9899 | |
| 9900 | DLAED3 finds the roots of the secular equation, as defined by the |
| 9901 | values in D, W, and RHO, between 1 and K. It makes the |
| 9902 | appropriate calls to DLAED4 and then updates the eigenvectors by |
| 9903 | multiplying the matrix of eigenvectors of the pair of eigensystems |
| 9904 | being combined by the matrix of eigenvectors of the K-by-K system |
| 9905 | which is solved here. |
| 9906 | |
| 9907 | This code makes very mild assumptions about floating point |
| 9908 | arithmetic. It will work on machines with a guard digit in |
| 9909 | add/subtract, or on those binary machines without guard digits |
| 9910 | which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or Cray-2. |
| 9911 | It could conceivably fail on hexadecimal or decimal machines |
| 9912 | without guard digits, but we know of none. |
| 9913 | |
| 9914 | Arguments |
| 9915 | ========= |
| 9916 | |
| 9917 | K (input) INTEGER |
| 9918 | The number of terms in the rational function to be solved by |
| 9919 | DLAED4. K >= 0. |
| 9920 | |
| 9921 | N (input) INTEGER |