Indicator help request

["Lyle Cox" <lgpcox@xxxxxxxxx>]

I trying to duplicate the calculation of the variable moving average as
posted on page 489 of the 7.0 manual.

"VMA = (0.78*(volatility index) * close) + (1-0.078 * volatility
index)*yesterday's VMA
The absolute value of a 9-period Chande Momentum Oscillator is used for the
volatility index"

I enter the following indicator:
vi:=cmo( c,9 )
vma = (0.78*(vi) * C) + (1-0.078 * vi)*prev:
vma:

But it does not plot anything like Mov(c,9,var)
What am I doing wrong?

The reason I want to duplicate the variable moving average, is that I would
like to try differnt indicators for the "(volatility index)" part of the
formula.

Thanks
Lyle