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clacn2.f(3)			    LAPACK			   clacn2.f(3)

       clacn2.f -

       subroutine clacn2 (N, V, X, EST, KASE, ISAVE)
	   CLACN2 estimates the 1-norm of a square matrix, using reverse
	   communication for evaluating matrix-vector products.

Function/Subroutine Documentation
   subroutine clacn2 (integerN, complex, dimension( * )V, complex, dimension(
       * )X, realEST, integerKASE, integer, dimension( 3 )ISAVE)
       CLACN2 estimates the 1-norm of a square matrix, using reverse
       communication for evaluating matrix-vector products.


	    CLACN2 estimates the 1-norm of a square, complex matrix A.
	    Reverse communication is used for evaluating matrix-vector products.


		     N is INTEGER
		    The order of the matrix.  N >= 1.


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


		     X is COMPLEX array, dimension (N)
		    On an intermediate return, X should be overwritten by
			  A * X,   if KASE=1,
			  A**H * X,  if KASE=2,
		    where A**H is the conjugate transpose of A, and CLACN2 must be
		    re-called with all the other parameters unchanged.


		     EST is REAL
		    On entry with KASE = 1 or 2 and ISAVE(1) = 3, EST should be
		    unchanged from the previous call to CLACN2.
		    On exit, EST is an estimate (a lower bound) for norm(A).


		     KASE is INTEGER
		    On the initial call to CLACN2, 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**H * X.
		    On the final return from CLACN2, KASE will again be 0.


		     ISAVE is INTEGER array, dimension (3)
		    ISAVE is used to save variables between calls to SLACN2

	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

	   September 2012

       Further Details:

	     Originally named CONEST, dated March 16, 1988.

	     Last modified:  April, 1999

	     This is a thread safe version of CLACON, which uses the array ISAVE
	     in place of a SAVE statement, as follows:

		 JUMP	  ISAVE(1)
		 J	  ISAVE(2)
		 ITER	  ISAVE(3)

	   Nick Higham, University of Manchester

	   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.

       Definition at line 134 of file clacn2.f.

       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2			Tue Sep 25 2012			   clacn2.f(3)

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