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CLA_GBAMV(1LAPACK routine (version 3.2)				  CLA_GBAMV(1)

NAME
       CLA_GBAMV  -  performs  one  of	the  matrix-vector  operations	  y :=
       alpha*abs(A)*abs(x) + beta*abs(y),

SYNOPSIS
       SUBROUTINE CLA_GBAMV( TRANS, M, N, KL, KU, ALPHA, AB,  LDAB,  X,	 INCX,
			     BETA, Y, INCY )

	   IMPLICIT	     NONE

	   REAL		     ALPHA, BETA

	   INTEGER	     INCX, INCY, LDAB, M, N, KL, KU, TRANS

	   COMPLEX	     AB( LDAB, * ), X( * )

	   REAL		     Y( * )

PURPOSE
       SLA_GEAMV  performs one of the matrix-vector operations
	  or   y := alpha*abs(A)'*abs(x) + beta*abs(y),
       where  alpha and beta are scalars, x and y are vectors and A is an m by
       n matrix.
       This function is primarily used in calculating error bounds.   To  pro‐
       tect  against  underflow during evaluation, components in the resulting
       vector are perturbed away  from	zero  by  (N+1)	 times	the  underflow
       threshold.   To	prevent unnecessarily large errors for block-structure
       embedded in general matrices,
       "symbolically" zero components are not perturbed.  A zero entry is con‐
       sidered	"symbolic"  if	all multiplications involved in computing that
       entry have at least one zero multiplicand.

ARGUMENTS
       TRANS  - INTEGER
	      On entry, TRANS specifies the operation to be performed as  fol‐
	      lows:

       BLAS_NO_TRANS	  y := alpha*abs(A)*abs(x) + beta*abs(y)
			  BLAS_TRANS	       y   :=  alpha*abs(A')*abs(x)  +
			  beta*abs(y)
			  BLAS_CONJ_TRANS     y	 :=   alpha*abs(A')*abs(x)   +
			  beta*abs(y) Unchanged on exit.

       M      - INTEGER
	      On  entry,  M  specifies	the number of rows of the matrix A.  M
	      must be at least zero.  Unchanged on exit.

       N      - INTEGER
	      On entry, N specifies the number of columns of the matrix A.   N
	      must be at least zero.  Unchanged on exit.

       KL     - INTEGER
	      The number of subdiagonals within the band of A.	KL >= 0.

       KU     - INTEGER
	      The number of superdiagonals within the band of A.  KU >= 0.

       ALPHA  - REAL
	      On entry, ALPHA specifies the scalar alpha.  Unchanged on exit.

       A      - REAL		 array of DIMENSION ( LDA, n )
	      Before  entry,  the leading m by n part of the array A must con‐
	      tain the matrix of coefficients.	Unchanged on exit.

       LDA    - INTEGER
	      On entry, LDA specifies the first dimension of A as declared  in
	      the  calling  (sub)  program.  LDA must be at least max( 1, m ).
	      Unchanged on exit.

       X      - REAL		 array of DIMENSION at least
	      ( 1 + ( n - 1 )*abs( INCX ) ) when TRANS = 'N'  or  'n'  and  at
	      least  (	1  + ( m - 1 )*abs( INCX ) ) otherwise.	 Before entry,
	      the incremented array X must contain the vector x.  Unchanged on
	      exit.

       INCX   - INTEGER
	      On  entry,  INCX	specifies the increment for the elements of X.
	      INCX must not be zero.  Unchanged on exit.

       BETA   - REAL
	      On entry, BETA specifies the scalar beta. When BETA is  supplied
	      as zero then Y need not be set on input.	Unchanged on exit.

       Y      - REAL		 array of DIMENSION at least
	      (	 1  +  (  m - 1 )*abs( INCY ) ) when TRANS = 'N' or 'n' and at
	      least ( 1 + ( n - 1 )*abs( INCY )	 )  otherwise.	 Before	 entry
	      with  BETA  non-zero,  the  incremented array Y must contain the
	      vector y. On exit, Y is overwritten by the updated vector y.

       INCY   - INTEGER
	      On entry, INCY specifies the increment for the  elements	of  Y.
	      INCY  must  not  be zero.	 Unchanged on exit.  Level 2 Blas rou‐
	      tine.

    LAPACK routine (version 3.2) November 2008			  CLA_GBAMV(1)
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