_RSGAB(3F)_RSGAB(3F)NAME
RSGAB, SRSGAB - EISPACK routine. This subroutine calls the
recommended sequence of subroutines from the eigensystem subroutine
package (EISPACK) to find the eigenvalues and eigenvectors (if desired)
for the REAL SYMMETRIC generalized eigenproblem ABx = (LAMBDA)x.
SYNOPSYS
subroutine rsgab(nm, n, a, b, w, matz, z, fv1, fv2, ierr)
integer n, nm,ierr,matz
double precision a(nm,n),b(nm,n),w(n),z(nm,n),fv1(n),fv2(n)
subroutine srsgab(nm, n, a, b, w, matz, z, fv1, fv2, ierr)
integer n, nm,ierr,matz
real a(nm,n),b(nm,n),w(n),z(nm,n),fv1(n),fv2(n)DESCRIPTION
On Input
NM must be set to the row dimension of the two-dimensional array
parameters as declared in the calling program dimension statement.
N is the order of the matrices A and B.
A contains a real symmetric matrix.
B contains a positive definite real symmetric matrix.
MATZ is an integer variable set equal to zero if only eigenvalues are
desired. Otherwise it is set to any non-zero integer for both
eigenvalues and eigenvectors. On Output
W contains the eigenvalues in ascending order.
Z contains the eigenvectors if MATZ is not zero.
IERR is an integer output variable set equal to an error completion code
described in section 2B of the documentation. The normal completion code
is zero.
FV1 and FV2 are temporary storage arrays. Questions and comments should
be directed to B. S. Garbow, APPLIED MATHEMATICS DIVISION, ARGONNE
NATIONAL LABORATORY
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