All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class org.netlib.lapack.Dsygs2

java.lang.Object
   |
   +----org.netlib.lapack.Dsygs2

public class Dsygs2

extends Object

Following is the description from the original
Fortran source.  For each array argument, the Java
version will include an integer offset parameter, so
the arguments may not match the description exactly.
Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  Purpose
 *  =======
 *
 *  DSYGS2 reduces a real symmetric-definite generalized eigenproblem
 *  to standard form.
 *
 *  If ITYPE = 1, the problem is A*x = lambda*B*x,
 *  and A is overwritten by inv(U')*A*inv(U) or inv(L)*A*inv(L')
 *
 *  If ITYPE = 2 or 3, the problem is A*B*x = lambda*x or
 *  B*A*x = lambda*x, and A is overwritten by U*A*U` or L'*A*L.
 *
 *  B must have been previously factorized as U'*U or L*L' by DPOTRF.
 *
 *  Arguments
 *  =========
 *
 *  ITYPE   (input) INTEGER
 *          = 1: compute inv(U')*A*inv(U) or inv(L)*A*inv(L');
 *          = 2 or 3: compute U*A*U' or L'*A*L.
 *
 *  UPLO    (input) CHARACTER
 *          Specifies whether the upper or lower triangular part of the
 *          symmetric matrix A is stored, and how B has been factorized.
 *          = 'U':  Upper triangular
 *          = 'L':  Lower triangular
 *
 *  N       (input) INTEGER
 *          The order of the matrices A and B.  N >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the symmetric matrix A.  If UPLO = 'U', the leading
 *          n by n upper triangular part of A contains the upper
 *          triangular part of the matrix A, and the strictly lower
 *          triangular part of A is not referenced.  If UPLO = 'L', the
 *          leading n by n lower triangular part of A contains the lower
 *          triangular part of the matrix A, and the strictly upper
 *          triangular part of A is not referenced.
 *
 *          On exit, if INFO = 0, the transformed matrix, stored in the
 *          same format as A.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= max(1,N).
 *
 *  B       (input) DOUBLE PRECISION array, dimension (LDB,N)
 *          The triangular factor from the Cholesky factorization of B,
 *          as returned by DPOTRF.
 *
 *  LDB     (input) INTEGER
 *          The leading dimension of the array B.  LDB >= max(1,N).
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit.
 *          < 0:  if INFO = -i, the i-th argument had an illegal value.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Dsygs2()

dsygs2(int, String, int, double[], int, int, double[], int, int, intW)

 public Dsygs2()

 public static void dsygs2(int itype,
                           String uplo,
                           int n,
                           double a[],
                           int _a_offset,
                           int lda,
                           double b[],
                           int _b_offset,
                           int ldb,
                           intW info)

All Packages  Class Hierarchy  This Package  Previous  Next  Index