function InitializeDistances (dummy)
{
	summingVector = {4,1}["1"];
	return 0;
}

function ComputeDistanceFormula (s1,s2)
{
	GetDataInfo (siteDifferenceCount, filteredData, s1, s2, DISTANCE_AMBIG_OPTION);
	totalSitesCompared = (Transpose(summingVector)*(siteDifferenceCount*summingVector))[0];
	if (totalSitesCompared)
	{
		return 1-(siteDifferenceCount[0][0]+siteDifferenceCount[1][1]+siteDifferenceCount[2][2]+siteDifferenceCount[3][3])/totalSitesCompared;
	}
	return 1000;
}
