#ifdef __cplusplus extern "C" { #endif #include "lmp_f2c.h" static integer c__1 = 1; static integer c_n1 = -1; static integer c__3 = 3; static integer c__2 = 2; static doublereal c_b22 = -1.; static doublereal c_b23 = 1.; int dsytrd_(char *uplo, integer *n, doublereal *a, integer *lda, doublereal *d__, doublereal *e, doublereal *tau, doublereal *work, integer *lwork, integer *info, ftnlen uplo_len) { integer a_dim1, a_offset, i__1, i__2, i__3; integer i__, j, nb, kk, nx, iws; extern logical lsame_(char *, char *, ftnlen, ftnlen); integer nbmin, iinfo; logical upper; extern int dsytd2_(char *, integer *, doublereal *, integer *, doublereal *, doublereal *, doublereal *, integer *, ftnlen), dsyr2k_(char *, char *, integer *, integer *, doublereal *, doublereal *, integer *, doublereal *, integer *, doublereal *, doublereal *, integer *, ftnlen, ftnlen), dlatrd_(char *, integer *, integer *, doublereal *, integer *, doublereal *, doublereal *, doublereal *, integer *, ftnlen), xerbla_(char *, integer *, ftnlen); extern integer ilaenv_(integer *, char *, char *, integer *, integer *, integer *, integer *, ftnlen, ftnlen); integer ldwork, lwkopt; logical lquery; a_dim1 = *lda; a_offset = 1 + a_dim1; a -= a_offset; --d__; --e; --tau; --work; *info = 0; upper = lsame_(uplo, (char *)"U", (ftnlen)1, (ftnlen)1); lquery = *lwork == -1; if (!upper && !lsame_(uplo, (char *)"L", (ftnlen)1, (ftnlen)1)) { *info = -1; } else if (*n < 0) { *info = -2; } else if (*lda < max(1, *n)) { *info = -4; } else if (*lwork < 1 && !lquery) { *info = -9; } if (*info == 0) { nb = ilaenv_(&c__1, (char *)"DSYTRD", uplo, n, &c_n1, &c_n1, &c_n1, (ftnlen)6, (ftnlen)1); i__1 = 1, i__2 = *n * nb; lwkopt = max(i__1, i__2); work[1] = (doublereal)lwkopt; } if (*info != 0) { i__1 = -(*info); xerbla_((char *)"DSYTRD", &i__1, (ftnlen)6); return 0; } else if (lquery) { return 0; } if (*n == 0) { work[1] = 1.; return 0; } nx = *n; iws = 1; if (nb > 1 && nb < *n) { i__1 = nb, i__2 = ilaenv_(&c__3, (char *)"DSYTRD", uplo, n, &c_n1, &c_n1, &c_n1, (ftnlen)6, (ftnlen)1); nx = max(i__1, i__2); if (nx < *n) { ldwork = *n; iws = ldwork * nb; if (*lwork < iws) { i__1 = *lwork / ldwork; nb = max(i__1, 1); nbmin = ilaenv_(&c__2, (char *)"DSYTRD", uplo, n, &c_n1, &c_n1, &c_n1, (ftnlen)6, (ftnlen)1); if (nb < nbmin) { nx = *n; } } } else { nx = *n; } } else { nb = 1; } if (upper) { kk = *n - (*n - nx + nb - 1) / nb * nb; i__1 = kk + 1; i__2 = -nb; for (i__ = *n - nb + 1; i__2 < 0 ? i__ >= i__1 : i__ <= i__1; i__ += i__2) { i__3 = i__ + nb - 1; dlatrd_(uplo, &i__3, &nb, &a[a_offset], lda, &e[1], &tau[1], &work[1], &ldwork, (ftnlen)1); i__3 = i__ - 1; dsyr2k_(uplo, (char *)"N", &i__3, &nb, &c_b22, &a[i__ * a_dim1 + 1], lda, &work[1], &ldwork, &c_b23, &a[a_offset], lda, (ftnlen)1, (ftnlen)1); i__3 = i__ + nb - 1; for (j = i__; j <= i__3; ++j) { a[j - 1 + j * a_dim1] = e[j - 1]; d__[j] = a[j + j * a_dim1]; } } dsytd2_(uplo, &kk, &a[a_offset], lda, &d__[1], &e[1], &tau[1], &iinfo, (ftnlen)1); } else { i__2 = *n - nx; i__1 = nb; for (i__ = 1; i__1 < 0 ? i__ >= i__2 : i__ <= i__2; i__ += i__1) { i__3 = *n - i__ + 1; dlatrd_(uplo, &i__3, &nb, &a[i__ + i__ * a_dim1], lda, &e[i__], &tau[i__], &work[1], &ldwork, (ftnlen)1); i__3 = *n - i__ - nb + 1; dsyr2k_(uplo, (char *)"N", &i__3, &nb, &c_b22, &a[i__ + nb + i__ * a_dim1], lda, &work[nb + 1], &ldwork, &c_b23, &a[i__ + nb + (i__ + nb) * a_dim1], lda, (ftnlen)1, (ftnlen)1); i__3 = i__ + nb - 1; for (j = i__; j <= i__3; ++j) { a[j + 1 + j * a_dim1] = e[j]; d__[j] = a[j + j * a_dim1]; } } i__1 = *n - i__ + 1; dsytd2_(uplo, &i__1, &a[i__ + i__ * a_dim1], lda, &d__[i__], &e[i__], &tau[i__], &iinfo, (ftnlen)1); } work[1] = (doublereal)lwkopt; return 0; } #ifdef __cplusplus } #endif