Traders' Tips from TASC Magazine

Refining the Hilbert Indicator

The function, system, and indicator introduced in the articles "Refining the Hilbert Indicator", by John Ehlers, and "Optimizing with Hilbert Indicators", by Roger Darley, which appear in the November 2000 TASC issue, can be created in MetaStock 7.0 or higher with the use of the new MetaStock External Function (MSX) DLL Interface. The C++ code and MetaStock formula code is shown below:

MSX DLL C++ Code

// Main Calculation loop (begins after the fifth valid bar)
for( l_iCurrentBar = a_iFirstValid + 5;
l_iCurrentBar <= a_iLastValid;l_iCurrentBar++ )
{
	// Set Previous Bar counter
	l_iPreviousBar = l_iCurrentBar - 1;

	// Calculate Smoother and Detrender values
	l_pdSmoother[l_iCurrentBar] = (4 * a_pfPrice[l_iCurrentBar] + 3 * a_pfPrice[l_iPreviousBar] + 2 * a_pfPrice[l_iCurrentBar - 2] + a_pfPrice[l_iCurrentBar - 3])/10;
	l_pdDetrender[l_iCurrentBar] = (.25 * l_pdSmoother[l_iCurrentBar] + .75 * l_pdSmoother[l_iCurrentBar - 2] - .75 * l_pdSmoother[l_iCurrentBar - 4] - .25 * l_pdSmoother[l_iCurrentBar - 6])* double(.046f * a_pfPeriod[l_iPreviousBar] + .332f);

	// Calculate InPhase and Quadrature components
	l_pd_Q1[l_iCurrentBar] = (.25 * l_pdDetrender[l_iCurrentBar] + .75 * l_pdDetrender[l_iCurrentBar - 2] - .75 * l_pdDetrender[l_iCurrentBar - 4] - .25 * l_pdDetrender[l_iCurrentBar - 6]) * double(.046f * a_pfPeriod[l_iPreviousBar] + .332f);
	l_pd_I1[l_iCurrentBar] = l_pdDetrender[l_iCurrentBar - 3];

	// Advance the phase of l_pd_I1 and l_pd_Q1 by 90 degrees
	l_pd_jI[l_iCurrentBar] = .25 * l_pd_I1[l_iCurrentBar] + .75 * l_pd_I1[l_iCurrentBar - 2] - .75 * l_pd_I1[l_iCurrentBar - 4] - .25 * l_pd_I1[l_iCurrentBar - 6];
	l_pd_jQ[l_iCurrentBar] = .25 * l_pd_Q1[l_iCurrentBar] + .75 * l_pd_Q1[l_iCurrentBar - 2] - .75 * l_pd_Q1[l_iCurrentBar - 4] -.25 * l_pd_Q1[l_iCurrentBar - 6];

	// Phasor addition to equalize amplitude due to quadrature
	// calculations (and 3 bar averaging)
	l_pd_I2[l_iCurrentBar] = l_pd_I1[l_iCurrentBar] - l_pd_jQ[l_iCurrentBar];
	l_pd_Q2[l_iCurrentBar] = l_pd_Q1[l_iCurrentBar] + l_pd_jI[l_iCurrentBar];

	// Smooth I and Q components before applying the discriminator
	l_pd_I2[l_iCurrentBar] = ForceFloatRange (.15 * l_pd_I2[l_iCurrentBar] + .85 * l_pd_I2[l_iPreviousBar]);
	l_pd_Q2[l_iCurrentBar] = ForceFloatRange (.15 * l_pd_Q2[l_iCurrentBar] + .85 * l_pd_Q2[l_iPreviousBar]);

	// Homodyne Discriminator;
Complex Conjugate Multiply
	l_pd_X1[l_iCurrentBar] = l_pd_I2[l_iCurrentBar] * l_pd_I2[l_iPreviousBar];
	l_pd_X2[l_iCurrentBar] = l_pd_I2[l_iCurrentBar] * l_pd_Q2[l_iPreviousBar];
	l_pd_Y1[l_iCurrentBar] = l_pd_Q2[l_iCurrentBar] * l_pd_Q2[l_iPreviousBar];
	l_pd_Y2[l_iCurrentBar] = l_pd_Q2[l_iCurrentBar] * l_pd_I2[l_iPreviousBar];
	l_pd_Re[l_iCurrentBar] = l_pd_X1[l_iCurrentBar] + l_pd_Y1[l_iCurrentBar];
	l_pd_Im[l_iCurrentBar] = l_pd_X2[l_iCurrentBar] - l_pd_Y2[l_iCurrentBar];

	// Smooth to remove any undesired cross products
	l_pd_Re[l_iCurrentBar] = ForceFloatRange (.2 * l_pd_Re[l_iCurrentBar] + .8 * l_pd_Re[l_iPreviousBar]);
	l_pd_Im[l_iCurrentBar] = ForceFloatRange (.2 * l_pd_Im[l_iCurrentBar] + .8 * l_pd_Im[l_iPreviousBar]);

	// Compute Cycle Period
	if (l_pd_Im[l_iCurrentBar] != 0 && l_pd_Re[l_iCurrentBar] != 0) a_pfPeriod[l_iCurrentBar] = float (ForceFloatRange (360 / (atan(l_pd_Im[l_iCurrentBar] / l_pd_Re[l_iCurrentBar] ) * (180.0 / PI))));
	if (a_pfPeriod[l_iCurrentBar] >
1.5f *a_pfPeriod[l_iPreviousBar]) a_pfPeriod[l_iCurrentBar] = 1.5f * a_pfPeriod[l_iPreviousBar];
	if (a_pfPeriod[l_iCurrentBar] <
.67f *a_pfPeriod[l_iPreviousBar]) a_pfPeriod[l_iCurrentBar] = .67f * a_pfPeriod[l_iPreviousBar];
	if (a_pfPeriod[l_iCurrentBar] <
6 ) a_pfPeriod[l_iCurrentBar] = 6;
	if ( a_pfPeriod[l_iCurrentBar] >
50 ) a_pfPeriod[l_iCurrentBar] = 50;
	a_pfPeriod[l_iCurrentBar] = .2f * a_pfPeriod[l_iCurrentBar] + .8f * a_pfPeriod[l_iPreviousBar];
}
			

MetaStock Code

Hilbert Channel Breakout Indicator

entryk:=Input("Entry K", 0, 1, 0);
entryval:=Input("Entry val", 0, 100, 0);
exitk:= Input("Exit K", 0, 4.5, 0);
exitval:=Input("Entry val", 0, 100, 0);

ExtFml( "EnhancedHilbert.ChannelHigh", (HIGH+LOW)/2, entryk, entryval);
ExtFml( "EnhancedHilbert.ChannelLow", (HIGH+LOW)/2, exitk, exitval)

Hilbert Channel Breakout Signal

Enter Long:
H >
ExtFml( "EnhancedHilbert.ChannelHigh",(HIGH+LOW)/2, 0, 15)

Enter Short:
L <
ExtFml( "EnhancedHilbert.ChannelLow",(HIGH+LOW)/2, 0, 15)

Click the links below to download the sample source code.

Dec2000EHilbertSetup.exe
Dec2000EnHilbertMSXSrc.ZIP