Normalize & Compliment

[jdtoellner]

Please post an example of the Normalize and Compliment functions for DSL_Dmatrix.

[shooltz[BayesFusion]]

Here's the example for the Normalize method. Note that there are also overloads with single integer (representing the linear index into the matrix) and with no parameters (all columns are normalized).

Code: Select all

int testNormalize()
{
	DSL_network net;

	// hepar.xdsl is distributed with GeNIe. Your path will be different!
	int res = net.ReadFile("d:/tmpx/hepar.xdsl");
	if (DSL_OKAY != res)
	{
		return res;
	}

	int h = net.FindNode("ESR");
	if (h < 0)
	{
		return h;
	}


	// 'live' access to ESR's definition. 
	DSL_Dmatrix & mtx = *net.GetNode(h)->Definition()->GetMatrix();

	// select arbitrary coordinates for the CPT
	// in this example, this is the second-to-last column
	DSL_intArray coords;
	coords.Add(1); // PBC = absent
	coords.Add(2); // ChHepatitis = absent
	coords.Add(1); // Steatosis = absent
	coords.Add(0); // Hyperbilirubinemia = present
	coords.Add(0); // final coordinate required, this is index of ESR's outcome

	printf("Original values in the CPT:\n");
	int base = mtx.CoordinatesToIndex(coords);
	for (int i = 0; i < 3; i++)
	{
		printf("%d, %Lg\n", i, mtx[base + i]);
	}
	

	// write arbitrary values, these will be normalized to ensure total==1
	mtx[coords] = 2;
	mtx.NextCoordinates(coords);
	mtx[coords] = 1;
	mtx.NextCoordinates(coords);
	mtx[coords] = 5;

	// Normalize ignores the last coordinate, will replace it with zero anyway
	mtx.Normalize(coords);

	// [2,1,5] should get normalized to 2/8 (0.25), 1/8 (0.125), 5/8 (0.625)
	// rewind back to 0th outcome in the specific CPT column
	printf("Modified values in the CPT:\n");
	for (int i = 0; i < 3; i++)
	{
		printf("%d, %Lg\n", i, mtx[base + i]);
		mtx.NextCoordinates(coords);
	}

	return DSL_OKAY;
}

[shooltz[BayesFusion]]

And here's the example for the Complement method.

Code: Select all

int testComplement()
{
	DSL_network net;

	// hepar.xdsl is distributed with GeNIe. Your path will be different!
	int res = net.ReadFile("d:/tmpx/hepar.xdsl");
	if (DSL_OKAY != res)
	{
		return res;
	}

	int h = net.FindNode("ESR");
	if (h < 0)
	{
		return h;
	}


	// 'live' access to ESR's definition. 
	DSL_Dmatrix & mtx = *net.GetNode(h)->Definition()->GetMatrix();

	// select arbitrary coordinates for the CPT
	// in this example, this is the second-to-last column
	DSL_intArray coords;
	coords.Add(1); // PBC = absent
	coords.Add(2); // ChHepatitis = absent
	coords.Add(1); // Steatosis = absent
	coords.Add(0); // Hyperbilirubinemia = present
	coords.Add(0); // final coordinate required, this is index of ESR's outcome

	printf("Original values in the CPT:\n");
	int base = mtx.CoordinatesToIndex(coords);
	for (int i = 0; i < 3; i++)
	{
		printf("%d, %Lg\n", i, mtx[base + i]);
	}


	// write arbitrary values to 0th and 2nd entry. 
	mtx[base] = 0.21;
	mtx[base + 2] = 0.33;

	// we'll be complementing the column by changing 1st entry
	coords[coords.NumItems() - 1] = 1;
	mtx.Complement(coords);

	// [0.21, x, 0.33] should change to [0.21, 0.46, 0.33]
	printf("Modified values in the CPT:\n");
	for (int i = 0; i < 3; i++)
	{
		printf("%d, %Lg\n", i, mtx[base + i]);
		mtx.NextCoordinates(coords);
	}

	return DSL_OKAY;
}