amibroker

HomeKnowledge Base

How to draw regression channel programatically

Built-in drawing tool allows to place regression channel on the chart manually and the study works on regular Close array as input. The power of AFL allows to automate this task and draw a customizable regression channel automatically in the chart or choose any custom array for calculation.

Here is a sample coding solution showing how to code Standard Deviation based channel. The Parameters dialog allows to control the array the channel is based upon, number of periods used for calculation, position and width of the channel.

lookback Param"Look back"201200);
shift Param"Shift"0020);
multiplier Param"Width"10.2550.25 );
color ParamColor"Color"colorRed );
style ParamStyle"Style"styleLine styleDots );
pricestyle ParamStyle"Price style"styleBar styleThickmaskPrice );
//
// price chart
PlotClose"Close"colorDefaultpricestyle );
//
array = ParamField"Price field", -);
//
BarIndex() + 1;
lastx LastValue) - shift;
//
// compute linear regression coefficients
aa LastValueRefLinRegIntercept( array, lookback ), -shift ) );
bb LastValueRefLinRegSlope( array, lookback ), -shift ) );
//
// the equation for straight line
Aa bb * ( - ( Lastx lookback ) );
//
width LastValueRefStDev( array, lookback ), -shift ) );
//
drawit > ( lastx lookback ) AND BarIndex() < Lastx;
//
// draw regression line...
PlotIIfdrawityNull ), "LinReg"colorstyle );
// ... and channel
PlotIIfdrawitwidth*multiplier Null ), "LinReg UP"colorstyle );
PlotIIfdrawitwidth*multiplier Null ), "LinReg DN"colorstyle );

Here is the picture that shows how it looks:

Regression in AFL

Comments are closed.