public class SSYGS2
- extends java.lang.Object
SSYGS2 is a simplified interface to the JLAPACK routine ssygs2.
This interface converts Java-style 2D row-major arrays into
the 1D column-major linearized arrays expected by the lower
level JLAPACK routines. Using this interface also allows you
to omit offset and leading dimension arguments. However, because
of these conversions, these routines will be slower than the low
level ones. Following is the description from the original Fortran
source. Contact email@example.com with any questions.
* SSYGS2 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 SPOTRF.
* 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) REAL 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) REAL array, dimension (LDB,N)
* The triangular factor from the Cholesky factorization of B,
* as returned by SPOTRF.
* 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 ..
|Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
public static void SSYGS2(int itype,