-=item B<STACK> : I<vname> # I<color> [ :I<legend> ]
-
-I<Deprecated. Use the B<STACK> modifiers on the other commands.>
-I<Note: the comments on stacking are still valid...>
-Repeats the last B<LINEx> or B<AREA> however it doesn't start at the
-x-axis but rather on top of the previous element. This implies that
-there needs to be something to stack on. An invisible B<LINEx> or
-B<AREA> is something you can stack on, an unknown value is not!
-
-Note: When you stack on something that was I<unknown>, the whole
-stack will be I<unknown> for that point in time. If the beginning
-is undefined, there's no way to end somewhere... If you want to
-graph this stacked variable anyway you need to make sure that the
-B<LINEx> or B<AREA> it gets stacked on is not unknown. Use a CDEF
-instruction with B<IF> and B<UN> to do so.
-
-=item B<PART> : I<vname> B<#> I<rrggbbaa> [ B<:> I<legend> ]
-
-B<RRDtool> has now support for B<pie charts>. If you include the
-B<PART> command, the canvas is extended to make room for a chart
-The size of the canvas is determined by the lesser of
-L<width and height|rrdgraph/item_Size>.
-
-Pie parts will be concatenated, the first one will start at the
-top and parts will be created clockwise. The size of the part
-is defined by the value part of the L<VDEF|rrdgraph_data/VDEF>
-function. It should return a number between 0 and 100, being a
-percentage. Providing wrong input will produce undefined results.
-