anchor.diff:  				&	matmul(xeof(i, zistart:ziend), zpc)
   		end do
   	end if
  -
  -!	Obsolete formulation using too much memory
  -!	ffrec = matmul( xeof(:, zistart:ziend), transpose(pc(:, zistart:ziend)) )
   
   	end subroutine sl_pcarec
   
  
positive.code: 				zff(:,i) = zff(:,i) * ww(:)
  			end do
  		end if
  		pc = matmul( transpose(zff), zeof)
  		do i = 1, nkeep
  			pc(:,i) = pc(:,i) / dot_product(zeof(:,i)**2, ww(:))
  		end do
  
negative.code: 	real, allocatable :: wff(:,:), ww(:), zeof(:,:), zff(:,:)
  	real, allocatable :: eig(:)
  	integer           :: zuseteof, znkeepmax, i,j
  real                  :: t1,t2
  
  	! Setups
  	! ======
  