amvwap2 and stddev function

[ljr500]

I'm trying to use the amvwap2 study (by Alexis C. Montenegro) along with his stddev study - amStdDev( ) to plot std deviation bands (1,2,3) around the vwap. It seems like it uses an internal global to return the vwap series. It doesn't seem like this will work with the amStdDev() function.

Am I correct? Will I have to iterate through the vwap series and pass the data onto the amstddev() function and then return a new series to plot?

Thanks for any help.