Esempio n. 1
    def sell(self, quantity, seller):

        """Sell the specified quantity

        we assume that when we sell, somebody else buys it so the amount issued doesn't change
        @param quantity:
        @param seller:
        @return: the quantity sold and the realised amount

        # see how much this seller has
        current = network.get_asset_holding(self.simInfo, self, seller)
        # scale the quantity if necessary
        quantity = min(quantity, current)
        # don't allow negative sales
        if quantity <= 0.0:
            return 0.0, 0.0

        newH = current - quantity
        # calculate the price
        fireSaleFactor = self.get_param('fireSaleFactor', 0.0)
        if fireSaleFactor > 0.0:
            priceFactor = math.exp(-fireSaleFactor * quantity / self.issued)
            newPrice = self.currentPrice * priceFactor
        # update the holding
        network.set_asset_holding(self.simInfo, self, seller, newH)
        self.record_holding_history(seller, newH)

        return quantity, quantity * self.currentPrice
Esempio n. 2
    def buy(self, quantity, buyer):
        """Create a holding of the specified amount

        A holding is an edge in the asset network.
        The amount issued is the total created so far
        @param buyer:
        @param quantity:
        @return: the quantity actually bought and the consideration

        # don't allow negative purchases
        if quantity < 0.0:
            return 0.0, 0.0

        # see if this buyer already has some
        current = network.get_asset_holding(self.simInfo, self, buyer)
        newH = current + quantity
        network.set_asset_holding(self.simInfo, self, buyer, newH)
        self.issued += quantity
        self.record_holding_history(buyer, newH)

        return quantity, quantity * self.currentPrice