Need EL help - NumericSeries array possible?

["Alex Matulich" <alex@xxxxxxxxxxxxxx>]

I've run into a little EL coding problem.

I have a function with the following arguments:

inputs: Price[n](NumericArray), length(NumericSimple),
slope[m](NumericArrayRef);

What this function is supposed to do is calculate slopes of up to 30 data
streams -- I have data1 to data30 saved each bar into my Price[] array,
then I pass it to this function to update 30 slopes (passed by reference).

Within the function I need to reference previous values of the array
elements, like Price[j][2] to reference the j-th element of the Price[]
array 2 bars ago.

PowerEditor complains.  It tells me that I can't reference previous values
of simple variables.  And yet, I cannot figure out how to make this into a
series function so I *can* reference previous values in my array!

Any suggestions?

-Alex