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QRUPDATE: A LIBRARY FOR FAST UPDATING OF QR AND CHOLESKY DECOMPOSITIONS
-----------------------------------------------------------------------

The following operations are supported:

QR rank-1 update (qr1up)
	Updates the QR factorization after an additive rank-1 update to the
	original matrix (A = A + u*v'). Works for full & economized 
	factorization.
QR column insert (qrinc)
	Updates the QR factorization after an inserting a column to the
	original matrix. Works for full & economized factorization.
QR column delete (qrdec)
	Updates the QR factorization after an deleting a column from the
	original matrix. Works for full & economized factorization.
QR column shift (qrshc)
	Updates the QR factorization after a circular shift of columns in 
	the original matrix. Works for full & economized factorization.
QR row insert (qrinr)
	Updates the QR factorization after an inserting a row to the
	original matrix. Works for full factorization only.
QR row delete (qrder)
	Updates the QR factorization after an deleting a row from the
	original matrix. Works for full factorization only.

Cholesky rank-1 update (ch1up)
	Updates the Cholesky factorization after positive rank-1 update
	A = A + u*u'. 
Cholesky rank-1 downdate (ch1dn)
	Updates the Cholesky factorization after positive rank-1 downdate
	A = A - u*u'. 
Cholesky symmetric insert (chinx)
	Updates the Cholesky factorization after a symmetric column/row
	insertion.
Cholesky symmetric insert (chdex)
	Updates the Cholesky factorization after a symmetric column/row
	deletion.
Cholesky symmetric shift (chshx)
	Updates the Cholesky factorization after a symmetric column/row
	left/right circular shift.

LU rank-1 update (lu1up)
	Updates the LU factorization after a rank-1 update (A = A + u*v.'). 
	No pivoting available. Faster than lup1up, but less stable.
LU pivoted rank-1 update (lup1up)
	Updates a row-pivoted LUP factorization after a rank-1 update
	(A = A + u*v.'). Also updates the row permutation matrix. Slower
	than lu1up, but more stable.

See the INSTALL file for installation details. Consult individual routines
for documentation.