DEMA is used for smoothing price series and is applied directly on a price chart of a financial security. 

instrument - defines Instrument of bars used as indicator data source.

period - defines Period of bars used as indicator data source.

shift - Defines which bar the indicator is calculated for: 0 - current unformed bar, 1 - previous bar and so on. Is of type Integer.

Time Period Integer - number of bars used in calculation.

DEMA Double - Indicator output (the result of indicator calculation).

IndicatorCall - connects indicator block with other blocks to continue the flow of Visual JForex strategy.

DEMA - Double Exponential Moving Average. The DEMA is a fast-acting moving average that is more responsive to market changes than a traditional moving average. It was developed by Patrick Mulloy to create a calculation that eliminated some of the lag associated with traditional moving averages. The formula is: DEMO = 2 * EMA - EMA(EMA).
Because EMA(EMA) is used in the calculation, DEMA needs 2 * period -1 samples to start producing values in contrast to the period samples needed by a regular EMA.

Usage in VisualForex:

 Add the DEMA indicator to the board, connect it with a block or start point and create double variable to store the DEMA indicator result. DEMA in VisualJForex: