# mono plane annihilator and its residual
#
subroutine moplan( agc, eps, data,n1,n2, niter, lag1,lag2, gap, aa,a1,a2, rr)
integer            agc,           n1,n2, niter, lag1,lag2, gap,    a1,a2
real	dot, lam,       eps, data(n1,n2),            aa(a1,a2),rr(n1*n2*2+a1*a2)
integer	i1, a12, r12, iter
temporary real da( a1,a2),  dr( n1*n2*2+a1*a2)
temporary real sa( a1,a2),  sr( n1*n2*2+a1*a2)
a12 = a1 * a2;		r12 = n1 * n2 * 2
call null( rr, r12+a12);	call null( aa, a12);	aa( lag1, lag2 ) = 1.
call null( dr, r12+a12);	call null( da, a12)
call         burg2 ( 0, 0, lag1,lag2, data,n1,n2, aa,a1,a2, rr       )
                           lam =  eps * sqrt( dot( r12, rr, rr))
call         ident ( 0, 0, lam,     a12,          aa,       rr(r12+1))
call         scale (    -1.,    r12+a12,                    rr       )
do iter= 0, niter {
	call burg2 ( 1, 0, lag1,lag2, data,n1,n2, da,a1,a2, rr       )
	call ident ( 1, 1, lam,     a12,          da,       rr(r12+1))

	do i1= 1, min0( a1, lag1+gap-1) {         da(i1,lag2)= 0.}
	call burg2 ( 0, 0, lag1,lag2, data,n1,n2, da,a1,a2, dr       )
	call ident ( 0, 0, lam,     a12,          da,       dr(r12+1))
	call cgstep( iter,  a12 , aa,da,sa,
			a12+r12 , rr,dr,sr )
	}
if( agc>0)   call scale( 1./sqrt(dot(r12,rr,rr)), a1*a2,aa)
call 	     burg2 ( 0, 0, lag1,lag2, data,n1,n2, aa,a1,a2, rr)
return; end