_MINFIT(3F)_MINFIT(3F)NAME
MINFIT, SMINFIT - EISPACK routine. This subroutine determines, towards
the solution of the linear
T system AX=B, the singular value decomposition A=USV of a real
T M by N rectangular matrix, forming U B rather than U. Householder
bidiagonalization and a variant of the QR algorithm are used.
SYNOPSYS
subroutine minfit(nm, m, n, a, w, ip, b, ierr, rv1)
integer nm, m, n, ip, ierr
double precision a(nm,n), w(n), b(nm,ip), rv1(n)
subroutine sminfit(nm, m, n, a, w, ip, b, ierr, rv1)
integer nm, m, n, ip, ierr
real a(nm,n), w(n), b(nm,ip), rv1(n)DESCRIPTION
On INPUT
NM must be set to the row dimension of two-dimensional array parameters
as declared in the calling program dimension statement. Note that NM
must be at least as large as the maximum of M and N.
M is the number of rows of A and B.
N is the number of columns of A and the order of V.
A contains the rectangular coefficient matrix of the system.
IP is the number of columns of B. IP can be zero.
B contains the constant column matrix of the system if IP is not zero.
Otherwise B is not referenced. On OUTPUT
A has been overwritten by the matrix V (orthogonal) of the decomposition
in its first N rows and columns. If an error exit is made, the columns
of V corresponding to indices of correct singular values should be
correct.
W contains the N (non-negative) singular values of A (the diagonal
elements of S). They are UNORDERED. If an error exit is made, the
singular values should be correct for indices IERR+1,IERR+2,...,N.
T
B has been overwritten by U B. If an error exit is made,
T the rows of U B corresponding to indices of correct singular values
should be correct.
IERR is set to Zero for normal return, K if the K-th
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_MINFIT(3F)_MINFIT(3F)
singular value has not been
determined after 30 iterations.
RV1 is a temporary storage array. Calls PYTHAG(A,B) for sqrt(A**2 +
B**2). Questions and comments should be directed to B. S. Garbow,
APPLIED MATHEMATICS DIVISION, ARGONNE NATIONAL LABORATORY
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