X-Git-Url: https://vcs.maemo.org/git/?a=blobdiff_plain;f=3rdparty%2Flapack%2Fstrti2.c;fp=3rdparty%2Flapack%2Fstrti2.c;h=40b283fec84044d34b2b46e129ad382708fb6640;hb=e4c14cdbdf2fe805e79cd96ded236f57e7b89060;hp=0000000000000000000000000000000000000000;hpb=454138ff8a20f6edb9b65a910101403d8b520643;p=opencv diff --git a/3rdparty/lapack/strti2.c b/3rdparty/lapack/strti2.c new file mode 100644 index 0000000..40b283f --- /dev/null +++ b/3rdparty/lapack/strti2.c @@ -0,0 +1,170 @@ +#include "clapack.h" + +/* Table of constant values */ + +static integer c__1 = 1; + +/* Subroutine */ int strti2_(char *uplo, char *diag, integer *n, real *a, + integer *lda, integer *info) +{ + /* System generated locals */ + integer a_dim1, a_offset, i__1, i__2; + + /* Local variables */ + integer j; + real ajj; + extern logical lsame_(char *, char *); + extern /* Subroutine */ int sscal_(integer *, real *, real *, integer *); + logical upper; + extern /* Subroutine */ int strmv_(char *, char *, char *, integer *, + real *, integer *, real *, integer *), + xerbla_(char *, integer *); + logical nounit; + + +/* -- LAPACK routine (version 3.1) -- */ +/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */ +/* November 2006 */ + +/* .. Scalar Arguments .. */ +/* .. */ +/* .. Array Arguments .. */ +/* .. */ + +/* Purpose */ +/* ======= */ + +/* STRTI2 computes the inverse of a real upper or lower triangular */ +/* matrix. */ + +/* This is the Level 2 BLAS version of the algorithm. */ + +/* Arguments */ +/* ========= */ + +/* UPLO (input) CHARACTER*1 */ +/* Specifies whether the matrix A is upper or lower triangular. */ +/* = 'U': Upper triangular */ +/* = 'L': Lower triangular */ + +/* DIAG (input) CHARACTER*1 */ +/* Specifies whether or not the matrix A is unit triangular. */ +/* = 'N': Non-unit triangular */ +/* = 'U': Unit triangular */ + +/* N (input) INTEGER */ +/* The order of the matrix A. N >= 0. */ + +/* A (input/output) REAL array, dimension (LDA,N) */ +/* On entry, the triangular matrix A. If UPLO = 'U', the */ +/* leading n by n upper triangular part of the array A contains */ +/* the upper triangular matrix, and the strictly lower */ +/* triangular part of A is not referenced. If UPLO = 'L', the */ +/* leading n by n lower triangular part of the array A contains */ +/* the lower triangular matrix, and the strictly upper */ +/* triangular part of A is not referenced. If DIAG = 'U', the */ +/* diagonal elements of A are also not referenced and are */ +/* assumed to be 1. */ + +/* On exit, the (triangular) inverse of the original matrix, in */ +/* the same storage format. */ + +/* LDA (input) INTEGER */ +/* The leading dimension of the array A. LDA >= max(1,N). */ + +/* INFO (output) INTEGER */ +/* = 0: successful exit */ +/* < 0: if INFO = -k, the k-th argument had an illegal value */ + +/* ===================================================================== */ + +/* .. Parameters .. */ +/* .. */ +/* .. Local Scalars .. */ +/* .. */ +/* .. External Functions .. */ +/* .. */ +/* .. External Subroutines .. */ +/* .. */ +/* .. Intrinsic Functions .. */ +/* .. */ +/* .. Executable Statements .. */ + +/* Test the input parameters. */ + + /* Parameter adjustments */ + a_dim1 = *lda; + a_offset = 1 + a_dim1; + a -= a_offset; + + /* Function Body */ + *info = 0; + upper = lsame_(uplo, "U"); + nounit = lsame_(diag, "N"); + if (! upper && ! lsame_(uplo, "L")) { + *info = -1; + } else if (! nounit && ! lsame_(diag, "U")) { + *info = -2; + } else if (*n < 0) { + *info = -3; + } else if (*lda < max(1,*n)) { + *info = -5; + } + if (*info != 0) { + i__1 = -(*info); + xerbla_("STRTI2", &i__1); + return 0; + } + + if (upper) { + +/* Compute inverse of upper triangular matrix. */ + + i__1 = *n; + for (j = 1; j <= i__1; ++j) { + if (nounit) { + a[j + j * a_dim1] = 1.f / a[j + j * a_dim1]; + ajj = -a[j + j * a_dim1]; + } else { + ajj = -1.f; + } + +/* Compute elements 1:j-1 of j-th column. */ + + i__2 = j - 1; + strmv_("Upper", "No transpose", diag, &i__2, &a[a_offset], lda, & + a[j * a_dim1 + 1], &c__1); + i__2 = j - 1; + sscal_(&i__2, &ajj, &a[j * a_dim1 + 1], &c__1); +/* L10: */ + } + } else { + +/* Compute inverse of lower triangular matrix. */ + + for (j = *n; j >= 1; --j) { + if (nounit) { + a[j + j * a_dim1] = 1.f / a[j + j * a_dim1]; + ajj = -a[j + j * a_dim1]; + } else { + ajj = -1.f; + } + if (j < *n) { + +/* Compute elements j+1:n of j-th column. */ + + i__1 = *n - j; + strmv_("Lower", "No transpose", diag, &i__1, &a[j + 1 + (j + + 1) * a_dim1], lda, &a[j + 1 + j * a_dim1], &c__1); + i__1 = *n - j; + sscal_(&i__1, &ajj, &a[j + 1 + j * a_dim1], &c__1); + } +/* L20: */ + } + } + + return 0; + +/* End of STRTI2 */ + +} /* strti2_ */