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LAPACK version 3.0
zlacon(3)

PURPOSE
  ZLACON - estimate the 1-norm of a square, complex matrix A

SYNTAX
  SUBROUTINE ZLACON( N, V, X, EST, KASE )

      INTEGER	     KASE, N

      DOUBLE	     PRECISION EST

      COMPLEX*16     V( N ), X( N )

DESCRIPTION
  ZLACON estimates the 1-norm of a square, complex matrix A. Reverse
  communication is used for evaluating matrix-vector products.

ARGUMENTS
  N	 (input) INTEGER
	 The order of the matrix.  N >= 1.

  V	 (workspace) COMPLEX*16 array, dimension (N)
	 On the final return, V = A*W,	where  EST = norm(V)/norm(W) (W is
	 not returned).

  X	 (input/output) COMPLEX*16 array, dimension (N)
	 On an intermediate return, X should be overwritten by A * X,	if
	 KASE=1, A' * X,  if KASE=2, where A' is the conjugate transpose of
	 A, and ZLACON must be re-called with all the other parameters
	 unchanged.

  EST	 (output) DOUBLE PRECISION
	 An estimate (a lower bound) for norm(A).

  KASE	 (input/output) INTEGER
	 On the initial call to ZLACON, KASE should be 0.  On an intermediate
	 return, KASE will be 1 or 2, indicating whether X should be
	 overwritten by A * X  or A' * X.  On the final return from ZLACON,
	 KASE will again be 0.

FURTHER DETAILS
  Contributed by Nick Higham, University of Manchester.
  Originally named CONEST, dated March 16, 1988.

  Reference: N.J. Higham, "FORTRAN codes for estimating the one-norm of a
  real or complex matrix, with applications to condition estimation", ACM
  Trans. Math. Soft., vol. 14, no. 4, pp. 381-396, December 1988.

  Last modified:  April, 1999