/**
* Initializes the specified {@link Connections} object which contains the memory and structural
* anatomy this spatial pooler uses to implement its algorithms.
*
* @param c a {@link Connections} object
*/
public void init(Connections c) {
if (c.getNumActiveColumnsPerInhArea() == 0
&& (c.getLocalAreaDensity() == 0 || c.getLocalAreaDensity() > 0.5)) {
throw new InvalidSPParamValueException("Inhibition parameters are invalid");
}
c.doSpatialPoolerPostInit();
initMatrices(c);
connectAndConfigureInputs(c);
}
/**
* Performs inhibition. This method calculates the necessary values needed to actually perform
* inhibition and then delegates the task of picking the active columns to helper functions.
*
* @param c the {@link Connections} matrix
* @param overlaps an array containing the overlap score for each column. The overlap score for a
* column is defined as the number of synapses in a "connected state" (connected synapses)
* that are connected to input bits which are turned on.
* @return
*/
public int[] inhibitColumns(Connections c, double[] overlaps) {
overlaps = Arrays.copyOf(overlaps, overlaps.length);
double density;
double inhibitionArea;
if ((density = c.getLocalAreaDensity()) <= 0) {
inhibitionArea = Math.pow(2 * c.getInhibitionRadius() + 1, c.getColumnDimensions().length);
inhibitionArea = Math.min(c.getNumColumns(), inhibitionArea);
density = c.getNumActiveColumnsPerInhArea() / inhibitionArea;
density = Math.min(density, 0.5);
}
// Add our fixed little bit of random noise to the scores to help break ties.
// ArrayUtils.d_add(overlaps, c.getTieBreaker());
if (c.getGlobalInhibition()
|| c.getInhibitionRadius() > ArrayUtils.max(c.getColumnDimensions())) {
return inhibitColumnsGlobal(c, overlaps, density);
}
return inhibitColumnsLocal(c, overlaps, density);
}
