getc2 - getc2: triangular factor, with complete pivoting

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subroutinecgetc2(integern,complex,dimension(lda,*)a,integerlda,integer,dimension(*)ipiv,integer,dimension(*)jpiv,integerinfo)CGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix. Purpose: CGETC2 computes an LU factorization, using complete pivoting, of the n-by-n matrix A. The factorization has the form A = P * L * U * Q, where P and Q are permutation matrices, L is lower triangular with unit diagonal elements and U is upper triangular. This is a level 1 BLAS version of the algorithm. ParametersN N is INTEGER The order of the matrix A. N >= 0. A A is COMPLEX array, dimension (LDA, N) On entry, the n-by-n matrix to be factored. On exit, the factors L and U from the factorization A = P*L*U*Q; the unit diagonal elements of L are not stored. If U(k, k) appears to be less than SMIN, U(k, k) is given the value of SMIN, giving a nonsingular perturbed system. LDA LDA is INTEGER The leading dimension of the array A. LDA >= max(1, N). IPIV IPIV is INTEGER array, dimension (N). The pivot indices; for 1 <= i <= N, row i of the matrix has been interchanged with row IPIV(i). JPIV JPIV is INTEGER array, dimension (N). The pivot indices; for 1 <= j <= N, column j of the matrix has been interchanged with column JPIV(j). INFO INFO is INTEGER = 0: successful exit > 0: if INFO = k, U(k, k) is likely to produce overflow if one tries to solve for x in Ax = b. So U is perturbed to avoid the overflow. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Contributors: Bo Kagstrom and Peter Poromaa, Department of Computing Science, Umea University, S-901 87 Umea, Sweden. subroutinedgetc2(integern,doubleprecision,dimension(lda,*)a,integerlda,integer,dimension(*)ipiv,integer,dimension(*)jpiv,integerinfo)DGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix. Purpose: DGETC2 computes an LU factorization with complete pivoting of the n-by-n matrix A. The factorization has the form A = P * L * U * Q, where P and Q are permutation matrices, L is lower triangular with unit diagonal elements and U is upper triangular. This is the Level 2 BLAS algorithm. ParametersN N is INTEGER The order of the matrix A. N >= 0. A A is DOUBLE PRECISION array, dimension (LDA, N) On entry, the n-by-n matrix A to be factored. On exit, the factors L and U from the factorization A = P*L*U*Q; the unit diagonal elements of L are not stored. If U(k, k) appears to be less than SMIN, U(k, k) is given the value of SMIN, i.e., giving a nonsingular perturbed system. LDA LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N). IPIV IPIV is INTEGER array, dimension(N). The pivot indices; for 1 <= i <= N, row i of the matrix has been interchanged with row IPIV(i). JPIV JPIV is INTEGER array, dimension(N). The pivot indices; for 1 <= j <= N, column j of the matrix has been interchanged with column JPIV(j). INFO INFO is INTEGER = 0: successful exit > 0: if INFO = k, U(k, k) is likely to produce overflow if we try to solve for x in Ax = b. So U is perturbed to avoid the overflow. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Contributors: Bo Kagstrom and Peter Poromaa, Department of Computing Science, Umea University, S-901 87 Umea, Sweden. subroutinesgetc2(integern,real,dimension(lda,*)a,integerlda,integer,dimension(*)ipiv,integer,dimension(*)jpiv,integerinfo)SGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix. Purpose: SGETC2 computes an LU factorization with complete pivoting of the n-by-n matrix A. The factorization has the form A = P * L * U * Q, where P and Q are permutation matrices, L is lower triangular with unit diagonal elements and U is upper triangular. This is the Level 2 BLAS algorithm. ParametersN N is INTEGER The order of the matrix A. N >= 0. A A is REAL array, dimension (LDA, N) On entry, the n-by-n matrix A to be factored. On exit, the factors L and U from the factorization A = P*L*U*Q; the unit diagonal elements of L are not stored. If U(k, k) appears to be less than SMIN, U(k, k) is given the value of SMIN, i.e., giving a nonsingular perturbed system. LDA LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N). IPIV IPIV is INTEGER array, dimension(N). The pivot indices; for 1 <= i <= N, row i of the matrix has been interchanged with row IPIV(i). JPIV JPIV is INTEGER array, dimension(N). The pivot indices; for 1 <= j <= N, column j of the matrix has been interchanged with column JPIV(j). INFO INFO is INTEGER = 0: successful exit > 0: if INFO = k, U(k, k) is likely to produce overflow if we try to solve for x in Ax = b. So U is perturbed to avoid the overflow. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Contributors: Bo Kagstrom and Peter Poromaa, Department of Computing Science, Umea University, S-901 87 Umea, Sweden. subroutinezgetc2(integern,complex*16,dimension(lda,*)a,integerlda,integer,dimension(*)ipiv,integer,dimension(*)jpiv,integerinfo)ZGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix. Purpose: ZGETC2 computes an LU factorization, using complete pivoting, of the n-by-n matrix A. The factorization has the form A = P * L * U * Q, where P and Q are permutation matrices, L is lower triangular with unit diagonal elements and U is upper triangular. This is a level 1 BLAS version of the algorithm. ParametersN N is INTEGER The order of the matrix A. N >= 0. A A is COMPLEX*16 array, dimension (LDA, N) On entry, the n-by-n matrix to be factored. On exit, the factors L and U from the factorization A = P*L*U*Q; the unit diagonal elements of L are not stored. If U(k, k) appears to be less than SMIN, U(k, k) is given the value of SMIN, giving a nonsingular perturbed system. LDA LDA is INTEGER The leading dimension of the array A. LDA >= max(1, N). IPIV IPIV is INTEGER array, dimension (N). The pivot indices; for 1 <= i <= N, row i of the matrix has been interchanged with row IPIV(i). JPIV JPIV is INTEGER array, dimension (N). The pivot indices; for 1 <= j <= N, column j of the matrix has been interchanged with column JPIV(j). INFO INFO is INTEGER = 0: successful exit > 0: if INFO = k, U(k, k) is likely to produce overflow if one tries to solve for x in Ax = b. So U is perturbed to avoid the overflow. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Contributors: Bo Kagstrom and Peter Poromaa, Department of Computing Science, Umea University, S-901 87 Umea, Sweden.

getc2 - getc2: triangular factor, with complete pivoting

Functions subroutine cgetc2 (n, a, lda, ipiv, jpiv, info) CGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix. subroutine dgetc2 (n, a, lda, ipiv, jpiv, info) DGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix. subroutine sgetc2 (n, a, lda, ipiv, jpiv, info) SGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix. subroutine zgetc2 (n, a, lda, ipiv, jpiv, info) ZGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix.