#ifdef __cplusplus extern "C" { #endif #include "lmp_f2c.h" static integer c__1 = 1; int dtrti2_(char *uplo, char *diag, integer *n, doublereal *a, integer *lda, integer *info, ftnlen uplo_len, ftnlen diag_len) { integer a_dim1, a_offset, i__1, i__2; integer j; doublereal ajj; extern int dscal_(integer *, doublereal *, doublereal *, integer *); extern logical lsame_(char *, char *, ftnlen, ftnlen); logical upper; extern int dtrmv_(char *, char *, char *, integer *, doublereal *, integer *, doublereal *, integer *, ftnlen, ftnlen, ftnlen), xerbla_(char *, integer *, ftnlen); logical nounit; a_dim1 = *lda; a_offset = 1 + a_dim1; a -= a_offset; *info = 0; upper = lsame_(uplo, (char *)"U", (ftnlen)1, (ftnlen)1); nounit = lsame_(diag, (char *)"N", (ftnlen)1, (ftnlen)1); if (!upper && !lsame_(uplo, (char *)"L", (ftnlen)1, (ftnlen)1)) { *info = -1; } else if (!nounit && !lsame_(diag, (char *)"U", (ftnlen)1, (ftnlen)1)) { *info = -2; } else if (*n < 0) { *info = -3; } else if (*lda < max(1, *n)) { *info = -5; } if (*info != 0) { i__1 = -(*info); xerbla_((char *)"DTRTI2", &i__1, (ftnlen)6); return 0; } if (upper) { i__1 = *n; for (j = 1; j <= i__1; ++j) { if (nounit) { a[j + j * a_dim1] = 1. / a[j + j * a_dim1]; ajj = -a[j + j * a_dim1]; } else { ajj = -1.; } i__2 = j - 1; dtrmv_((char *)"Upper", (char *)"No transpose", diag, &i__2, &a[a_offset], lda, &a[j * a_dim1 + 1], &c__1, (ftnlen)5, (ftnlen)12, (ftnlen)1); i__2 = j - 1; dscal_(&i__2, &ajj, &a[j * a_dim1 + 1], &c__1); } } else { for (j = *n; j >= 1; --j) { if (nounit) { a[j + j * a_dim1] = 1. / a[j + j * a_dim1]; ajj = -a[j + j * a_dim1]; } else { ajj = -1.; } if (j < *n) { i__1 = *n - j; dtrmv_((char *)"Lower", (char *)"No transpose", diag, &i__1, &a[j + 1 + (j + 1) * a_dim1], lda, &a[j + 1 + j * a_dim1], &c__1, (ftnlen)5, (ftnlen)12, (ftnlen)1); i__1 = *n - j; dscal_(&i__1, &ajj, &a[j + 1 + j * a_dim1], &c__1); } } } return 0; } #ifdef __cplusplus } #endif