Rik's Treehouse > Babbling in Binary > My Software > Orphanware > R2DToo > R2DToo Help > For the Programmer > nbrhdFractal

nbrhdFractal

Declaration
Parameters
Remarks
Example
See Also

Declaration

void __stdcall nbrhdFractal(
	int xRange,   // horizontal range
	int yRange,   // vertical range
	bool uplink,  // are my ancestors my neighbours?
	bool downlink // are my descendents my neighbours?
);

Parameters

xRange, yRange: Range of neighbourhood in horizontal and vertical directions, respectively.
uplink, downlink: Determines whether links are propagated up the fractal structure to the root or down to the leaves, or both. (Why computer scientists don't make good gardeners: they plant all their trees upside down!)

Remarks

This function is available through the API. It can be called within the model-supplied routine onSimCreate to generate a deterministic, scale-free network. The grid is divided into blocks of xRange×yRange sites linked to their "parents" (the top left site in each block). This pattern is repeated with blocks of xRange²yRange² and so on, up to the system size, when the uppermost left site is linked to all other sites of the lattice. By definition this creates a scale-free (power law) distribution of links.

Sample neighbourhood structure for xRange=yRange=2.

Example

void __stdcall setNbrhd(double *param) { // clustered, scale-free network nbrhdBlocks(2,3); // clustered nbrhdFractal(2,3,true,true); // scale-free }