Question regarding indicator development

[Xiongl80]

If I'm trying to create an indicator and define the variables

private double sma = 0;
private double k = 0;

And then in my OnBarUpdate(), I write

k = StdDev(5)[0] / StdDev(10)[0];

My next line I want to write sma = k times sma from one period ago, but I'm not sure how to call the value of sma from one period ago if it's a variable I've defined. Any help would be appreciated.

Thanks,
Lee

[NinjaTrader_Bertrand]

Lee, this would not be possible if you use just a double value - to access the series / history of a double you need to use a DataSeries object - http://www.ninjatrader.com/support/h...ries_class.htm