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Essential libraries for the Protelis language

There is a newer version: 17.7.1

module protelis:coord:sparsechoice
import protelis:coord:spreading

def breakUsingUids(uid, grain, metric) {
    // Return true if the current device is leader of the partition. Lead = current leader
    rep (lead <- uid) {
        distanceCompetition(G(uid == lead, 0, metric, (v) -> { v + metric.apply() }), lead, uid, grain, metric)
    } == uid
}

def distanceCompetition(d, lead, uid, grain, metric) {
    mux (d > grain) {
        // Device is far. Propose its id
        uid
    } else {
        let thr = 0.5 * grain;
        mux (d >= thr) {
            // Nearest neighbor in the second half (outer side) of the region. Do not challenge at all
            Infinity
        } else {
            // Challenge for this partition
            minHood(
                mux (nbr(d) + metric.apply() >= thr) {
                    // Device in the second half (outer side) of the region. Do not challenge at all
                    Infinity
                } else {
                    // Suggest the uid with the lowest random number
                    nbr(lead)
                }
            )
        }
    }
}

/**
 * Pair a random value to the device's id
 */
def randomUid() {
    rep (v <- [self.nextRandomDouble(), self.getDeviceUID()]) {
        [v.get(0), v.get(1)]
    }
}

/**
 * Devices compete against one another to become local leaders,
 * resulting  in  a  random  Voronoi  partition  with  a  characteristic
 * grain size.
 *
 * @param grain  num, partition dimension
 * @param metric () -> num, estimate distance from the leader
 * @return       bool, true if the current device is the leader, false otherwise
 */
public def S(grain, metric) {
    breakUsingUids(randomUid(), grain, metric)
}