new* VWAP equivalent, try to convert this into AFL!

["over_invested" <jparent@xxxx>]

to understand the setup for this idea, imagine a downward moving OBV
plot, then imagine a mov avg of it. the MA will be above. now draw a
horizontal line from the last point of the MA back to the OBV. plot
the close on that day the line touches the OBV. this should be similar
to a VWAP support/resistance line.

now, with some help from Equis, this is what the formula looks like in
metastock (for 21 day period):

If(OBV(C)<Mov(OBV(C),21,S),
ValueWhen(1,OBV(C)>LastValue(Mov(OBV(C),21,S)+PREV-PREV),C),
ValueWhen(1,OBV(C)<LastValue(Mov(OBV(C),21,S)+PREV-PREV),C));

don't try to figure it out. the +PREV-PREV used with LASTVALUE is a
workaround for a non-existent function. obviously, i would like to
convert this to AFL, but can't figure it out.