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| author | shmel1k <[email protected]> | 2022-09-02 12:44:59 +0300 |
|---|---|---|
| committer | shmel1k <[email protected]> | 2022-09-02 12:44:59 +0300 |
| commit | 90d450f74722da7859d6f510a869f6c6908fd12f (patch) | |
| tree | 538c718dedc76cdfe37ad6d01ff250dd930d9278 /contrib/libs/clapack/sgeqr2.c | |
| parent | 01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff) | |
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/sgeqr2.c')
| -rw-r--r-- | contrib/libs/clapack/sgeqr2.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/contrib/libs/clapack/sgeqr2.c b/contrib/libs/clapack/sgeqr2.c new file mode 100644 index 00000000000..7698d16b0c0 --- /dev/null +++ b/contrib/libs/clapack/sgeqr2.c @@ -0,0 +1,161 @@ +/* sgeqr2.f -- translated by f2c (version 20061008). + You must link the resulting object file with libf2c: + on Microsoft Windows system, link with libf2c.lib; + on Linux or Unix systems, link with .../path/to/libf2c.a -lm + or, if you install libf2c.a in a standard place, with -lf2c -lm + -- in that order, at the end of the command line, as in + cc *.o -lf2c -lm + Source for libf2c is in /netlib/f2c/libf2c.zip, e.g., + + http://www.netlib.org/f2c/libf2c.zip +*/ + +#include "f2c.h" +#include "blaswrap.h" + +/* Table of constant values */ + +static integer c__1 = 1; + +/* Subroutine */ int sgeqr2_(integer *m, integer *n, real *a, integer *lda, + real *tau, real *work, integer *info) +{ + /* System generated locals */ + integer a_dim1, a_offset, i__1, i__2, i__3; + + /* Local variables */ + integer i__, k; + real aii; + extern /* Subroutine */ int slarf_(char *, integer *, integer *, real *, + integer *, real *, real *, integer *, real *), xerbla_( + char *, integer *), slarfp_(integer *, real *, real *, + integer *, real *); + + +/* -- LAPACK routine (version 3.2) -- */ +/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */ +/* November 2006 */ + +/* .. Scalar Arguments .. */ +/* .. */ +/* .. Array Arguments .. */ +/* .. */ + +/* Purpose */ +/* ======= */ + +/* SGEQR2 computes a QR factorization of a real m by n matrix A: */ +/* A = Q * R. */ + +/* Arguments */ +/* ========= */ + +/* M (input) INTEGER */ +/* The number of rows of the matrix A. M >= 0. */ + +/* N (input) INTEGER */ +/* The number of columns of the matrix A. N >= 0. */ + +/* A (input/output) REAL array, dimension (LDA,N) */ +/* On entry, the m by n matrix A. */ +/* On exit, the elements on and above the diagonal of the array */ +/* contain the min(m,n) by n upper trapezoidal matrix R (R is */ +/* upper triangular if m >= n); the elements below the diagonal, */ +/* with the array TAU, represent the orthogonal matrix Q as a */ +/* product of elementary reflectors (see Further Details). */ + +/* LDA (input) INTEGER */ +/* The leading dimension of the array A. LDA >= max(1,M). */ + +/* TAU (output) REAL array, dimension (min(M,N)) */ +/* The scalar factors of the elementary reflectors (see Further */ +/* Details). */ + +/* WORK (workspace) REAL array, dimension (N) */ + +/* INFO (output) INTEGER */ +/* = 0: successful exit */ +/* < 0: if INFO = -i, the i-th argument had an illegal value */ + +/* Further Details */ +/* =============== */ + +/* The matrix Q is represented as a product of elementary reflectors */ + +/* Q = H(1) H(2) . . . H(k), where k = min(m,n). */ + +/* Each H(i) has the form */ + +/* H(i) = I - tau * v * v' */ + +/* where tau is a real scalar, and v is a real vector with */ +/* v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i), */ +/* and tau in TAU(i). */ + +/* ===================================================================== */ + +/* .. Parameters .. */ +/* .. */ +/* .. Local Scalars .. */ +/* .. */ +/* .. External Subroutines .. */ +/* .. */ +/* .. Intrinsic Functions .. */ +/* .. */ +/* .. Executable Statements .. */ + +/* Test the input arguments */ + + /* Parameter adjustments */ + a_dim1 = *lda; + a_offset = 1 + a_dim1; + a -= a_offset; + --tau; + --work; + + /* Function Body */ + *info = 0; + if (*m < 0) { + *info = -1; + } else if (*n < 0) { + *info = -2; + } else if (*lda < max(1,*m)) { + *info = -4; + } + if (*info != 0) { + i__1 = -(*info); + xerbla_("SGEQR2", &i__1); + return 0; + } + + k = min(*m,*n); + + i__1 = k; + for (i__ = 1; i__ <= i__1; ++i__) { + +/* Generate elementary reflector H(i) to annihilate A(i+1:m,i) */ + + i__2 = *m - i__ + 1; +/* Computing MIN */ + i__3 = i__ + 1; + slarfp_(&i__2, &a[i__ + i__ * a_dim1], &a[min(i__3, *m)+ i__ * a_dim1] +, &c__1, &tau[i__]); + if (i__ < *n) { + +/* Apply H(i) to A(i:m,i+1:n) from the left */ + + aii = a[i__ + i__ * a_dim1]; + a[i__ + i__ * a_dim1] = 1.f; + i__2 = *m - i__ + 1; + i__3 = *n - i__; + slarf_("Left", &i__2, &i__3, &a[i__ + i__ * a_dim1], &c__1, &tau[ + i__], &a[i__ + (i__ + 1) * a_dim1], lda, &work[1]); + a[i__ + i__ * a_dim1] = aii; + } +/* L10: */ + } + return 0; + +/* End of SGEQR2 */ + +} /* sgeqr2_ */ |
