anchor.diff:  	real, allocatable :: wff(:,:), ww(:), zeof(:,:), zff(:,:)
   	real, allocatable :: eig(:)
   	integer           :: zuseteof, znkeepmax, i,j
  +real                  :: t1,t2
   
   	! Setups
   	! ======
  
positive.code: 		! Back to S-EOFs
  		if(present(pc).or.present(xeof))then
  			allocate(zeof(ns,nkeep))
  			zeof = matmul(zff, cov(:,nt:nt-nkeep+1:-1))
  			deallocate(cov)
  			do i = 1, nkeep
  				zeof(:,i) = zeof(:,i) / sqrt(dot_product(ww(:), zeof(:,i)**2))
  
negative.code: 				&	matmul(xeof(i, zistart:ziend), zpc)
  		end do
  	end if
  
  	end subroutine sl_pcarec
  
  