!>
!> ZLA_GBAMV  performs one of the matrix-vector operations
!>
!>         y := alpha*abs(A)*abs(x) + beta*abs(y),
!>    or   y := alpha*abs(A)**T*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 protect 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,
!>  zero components are not perturbed.  A zero
!> entry is considered  if all multiplications involved
!> in computing that entry have at least one zero multiplicand.
!> 

TRANS

!>          TRANS is INTEGER
!>           On entry, TRANS specifies the operation to be performed as
!>           follows:
!>
!>             BLAS_NO_TRANS      y := alpha*abs(A)*abs(x) + beta*abs(y)
!>             BLAS_TRANS         y := alpha*abs(A**T)*abs(x) + beta*abs(y)
!>             BLAS_CONJ_TRANS    y := alpha*abs(A**T)*abs(x) + beta*abs(y)
!>
!>           Unchanged on exit.
!> 

M

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

N

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

KL

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

KU

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

ALPHA

!>          ALPHA is DOUBLE PRECISION
!>           On entry, ALPHA specifies the scalar alpha.
!>           Unchanged on exit.
!> 

AB

!>          AB is COMPLEX*16 array, dimension ( LDAB, n )
!>           Before entry, the leading m by n part of the array AB must
!>           contain the matrix of coefficients.
!>           Unchanged on exit.
!> 

LDAB

!>          LDAB is INTEGER
!>           On entry, LDAB specifies the first dimension of AB as declared
!>           in the calling (sub) program. LDAB must be at least
!>           max( 1, m ).
!>           Unchanged on exit.
!> 

X

!>          X is COMPLEX*16 array, dimension
!>           ( 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

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

BETA

!>          BETA is DOUBLE PRECISION
!>           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

!>          Y is DOUBLE PRECISION array, dimension
!>           ( 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.
!>           If either m or n is zero, then Y not referenced and the function
!>           performs a quick return.
!> 

INCY

!>          INCY is INTEGER
!>           On entry, INCY specifies the increment for the elements of
!>           Y. INCY must not be zero.
!>           Unchanged on exit.
!>
!>  Level 2 Blas routine.
!> 

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