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author | shmel1k <shmel1k@ydb.tech> | 2022-09-02 12:44:59 +0300 |
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committer | shmel1k <shmel1k@ydb.tech> | 2022-09-02 12:44:59 +0300 |
commit | 90d450f74722da7859d6f510a869f6c6908fd12f (patch) | |
tree | 538c718dedc76cdfe37ad6d01ff250dd930d9278 /contrib/libs/clapack/dgtts2.c | |
parent | 01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff) | |
download | ydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz |
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/dgtts2.c')
-rw-r--r-- | contrib/libs/clapack/dgtts2.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/contrib/libs/clapack/dgtts2.c b/contrib/libs/clapack/dgtts2.c new file mode 100644 index 0000000000..fce9cc8e8c --- /dev/null +++ b/contrib/libs/clapack/dgtts2.c @@ -0,0 +1,261 @@ +/* dgtts2.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" + +/* Subroutine */ int dgtts2_(integer *itrans, integer *n, integer *nrhs, + doublereal *dl, doublereal *d__, doublereal *du, doublereal *du2, + integer *ipiv, doublereal *b, integer *ldb) +{ + /* System generated locals */ + integer b_dim1, b_offset, i__1, i__2; + + /* Local variables */ + integer i__, j, ip; + doublereal temp; + + +/* -- LAPACK auxiliary routine (version 3.2) -- */ +/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */ +/* November 2006 */ + +/* .. Scalar Arguments .. */ +/* .. */ +/* .. Array Arguments .. */ +/* .. */ + +/* Purpose */ +/* ======= */ + +/* DGTTS2 solves one of the systems of equations */ +/* A*X = B or A'*X = B, */ +/* with a tridiagonal matrix A using the LU factorization computed */ +/* by DGTTRF. */ + +/* Arguments */ +/* ========= */ + +/* ITRANS (input) INTEGER */ +/* Specifies the form of the system of equations. */ +/* = 0: A * X = B (No transpose) */ +/* = 1: A'* X = B (Transpose) */ +/* = 2: A'* X = B (Conjugate transpose = Transpose) */ + +/* N (input) INTEGER */ +/* The order of the matrix A. */ + +/* NRHS (input) INTEGER */ +/* The number of right hand sides, i.e., the number of columns */ +/* of the matrix B. NRHS >= 0. */ + +/* DL (input) DOUBLE PRECISION array, dimension (N-1) */ +/* The (n-1) multipliers that define the matrix L from the */ +/* LU factorization of A. */ + +/* D (input) DOUBLE PRECISION array, dimension (N) */ +/* The n diagonal elements of the upper triangular matrix U from */ +/* the LU factorization of A. */ + +/* DU (input) DOUBLE PRECISION array, dimension (N-1) */ +/* The (n-1) elements of the first super-diagonal of U. */ + +/* DU2 (input) DOUBLE PRECISION array, dimension (N-2) */ +/* The (n-2) elements of the second super-diagonal of U. */ + +/* IPIV (input) INTEGER array, dimension (N) */ +/* The pivot indices; for 1 <= i <= n, row i of the matrix was */ +/* interchanged with row IPIV(i). IPIV(i) will always be either */ +/* i or i+1; IPIV(i) = i indicates a row interchange was not */ +/* required. */ + +/* B (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS) */ +/* On entry, the matrix of right hand side vectors B. */ +/* On exit, B is overwritten by the solution vectors X. */ + +/* LDB (input) INTEGER */ +/* The leading dimension of the array B. LDB >= max(1,N). */ + +/* ===================================================================== */ + +/* .. Local Scalars .. */ +/* .. */ +/* .. Executable Statements .. */ + +/* Quick return if possible */ + + /* Parameter adjustments */ + --dl; + --d__; + --du; + --du2; + --ipiv; + b_dim1 = *ldb; + b_offset = 1 + b_dim1; + b -= b_offset; + + /* Function Body */ + if (*n == 0 || *nrhs == 0) { + return 0; + } + + if (*itrans == 0) { + +/* Solve A*X = B using the LU factorization of A, */ +/* overwriting each right hand side vector with its solution. */ + + if (*nrhs <= 1) { + j = 1; +L10: + +/* Solve L*x = b. */ + + i__1 = *n - 1; + for (i__ = 1; i__ <= i__1; ++i__) { + ip = ipiv[i__]; + temp = b[i__ + 1 - ip + i__ + j * b_dim1] - dl[i__] * b[ip + + j * b_dim1]; + b[i__ + j * b_dim1] = b[ip + j * b_dim1]; + b[i__ + 1 + j * b_dim1] = temp; +/* L20: */ + } + +/* Solve U*x = b. */ + + b[*n + j * b_dim1] /= d__[*n]; + if (*n > 1) { + b[*n - 1 + j * b_dim1] = (b[*n - 1 + j * b_dim1] - du[*n - 1] + * b[*n + j * b_dim1]) / d__[*n - 1]; + } + for (i__ = *n - 2; i__ >= 1; --i__) { + b[i__ + j * b_dim1] = (b[i__ + j * b_dim1] - du[i__] * b[i__ + + 1 + j * b_dim1] - du2[i__] * b[i__ + 2 + j * b_dim1] + ) / d__[i__]; +/* L30: */ + } + if (j < *nrhs) { + ++j; + goto L10; + } + } else { + i__1 = *nrhs; + for (j = 1; j <= i__1; ++j) { + +/* Solve L*x = b. */ + + i__2 = *n - 1; + for (i__ = 1; i__ <= i__2; ++i__) { + if (ipiv[i__] == i__) { + b[i__ + 1 + j * b_dim1] -= dl[i__] * b[i__ + j * + b_dim1]; + } else { + temp = b[i__ + j * b_dim1]; + b[i__ + j * b_dim1] = b[i__ + 1 + j * b_dim1]; + b[i__ + 1 + j * b_dim1] = temp - dl[i__] * b[i__ + j * + b_dim1]; + } +/* L40: */ + } + +/* Solve U*x = b. */ + + b[*n + j * b_dim1] /= d__[*n]; + if (*n > 1) { + b[*n - 1 + j * b_dim1] = (b[*n - 1 + j * b_dim1] - du[*n + - 1] * b[*n + j * b_dim1]) / d__[*n - 1]; + } + for (i__ = *n - 2; i__ >= 1; --i__) { + b[i__ + j * b_dim1] = (b[i__ + j * b_dim1] - du[i__] * b[ + i__ + 1 + j * b_dim1] - du2[i__] * b[i__ + 2 + j * + b_dim1]) / d__[i__]; +/* L50: */ + } +/* L60: */ + } + } + } else { + +/* Solve A' * X = B. */ + + if (*nrhs <= 1) { + +/* Solve U'*x = b. */ + + j = 1; +L70: + b[j * b_dim1 + 1] /= d__[1]; + if (*n > 1) { + b[j * b_dim1 + 2] = (b[j * b_dim1 + 2] - du[1] * b[j * b_dim1 + + 1]) / d__[2]; + } + i__1 = *n; + for (i__ = 3; i__ <= i__1; ++i__) { + b[i__ + j * b_dim1] = (b[i__ + j * b_dim1] - du[i__ - 1] * b[ + i__ - 1 + j * b_dim1] - du2[i__ - 2] * b[i__ - 2 + j * + b_dim1]) / d__[i__]; +/* L80: */ + } + +/* Solve L'*x = b. */ + + for (i__ = *n - 1; i__ >= 1; --i__) { + ip = ipiv[i__]; + temp = b[i__ + j * b_dim1] - dl[i__] * b[i__ + 1 + j * b_dim1] + ; + b[i__ + j * b_dim1] = b[ip + j * b_dim1]; + b[ip + j * b_dim1] = temp; +/* L90: */ + } + if (j < *nrhs) { + ++j; + goto L70; + } + + } else { + i__1 = *nrhs; + for (j = 1; j <= i__1; ++j) { + +/* Solve U'*x = b. */ + + b[j * b_dim1 + 1] /= d__[1]; + if (*n > 1) { + b[j * b_dim1 + 2] = (b[j * b_dim1 + 2] - du[1] * b[j * + b_dim1 + 1]) / d__[2]; + } + i__2 = *n; + for (i__ = 3; i__ <= i__2; ++i__) { + b[i__ + j * b_dim1] = (b[i__ + j * b_dim1] - du[i__ - 1] * + b[i__ - 1 + j * b_dim1] - du2[i__ - 2] * b[i__ - + 2 + j * b_dim1]) / d__[i__]; +/* L100: */ + } + for (i__ = *n - 1; i__ >= 1; --i__) { + if (ipiv[i__] == i__) { + b[i__ + j * b_dim1] -= dl[i__] * b[i__ + 1 + j * + b_dim1]; + } else { + temp = b[i__ + 1 + j * b_dim1]; + b[i__ + 1 + j * b_dim1] = b[i__ + j * b_dim1] - dl[ + i__] * temp; + b[i__ + j * b_dim1] = temp; + } +/* L110: */ + } +/* L120: */ + } + } + } + +/* End of DGTTS2 */ + + return 0; +} /* dgtts2_ */ |