MatchMaking Example 3 (read matchmaking example 2 first):

Assume, that a car seller sells cars. A buyer is looking for a second hand car, but wants to pay not more than around $12000 and the cars should not have more than 15000 kilometers. Furthermore, he wants to give more priority to the price preference rather than to the kilometers preference. Additionally, the seller may provide discount to the cars. The more is the discount the less is the seller satisfied. Find the best match and for each match determine the discounted price.

The encoding is as follows:

(functional hasPrice)
(functional hasKM)

(implies Sedan Car)
(implies StationWagon Car)

# Seller's cars
(define-fuzzy-concept P12500 right-shoulder(0,50000,11250,12500)) # the seller prefers to sell it above $12500, but can go down to $11250, to a lesser degree of satisfacion
(define-fuzzy-concept KM18000 crisp(0,1000000,18000,18000))
(define-concept C455 (and Sedan (some hasPrice P12500) (some hasKM KM18000)))

(define-fuzzy-concept P12000 right-shoulder(0,50000,9600,12000))
(define-fuzzy-concept KM17000 crisp(0,1000000,17000,17000))
(define-concept C34 (and Sedan (some hasPrice P12000) (some hasKM KM17000)))

(define-fuzzy-concept P13000 right-shoulder(0,50000,10400,13000))
(define-fuzzy-concept KM16000 crisp(0,1000000,16000,16000))
(define-concept C1812 (and StationWagon (some hasPrice P13000) (some hasKM KM16000)))

# Buyer's preferencess

(define-fuzzy-concept BuyerCarPrice left-shoulder(0,50000,10000,14000))
(define-fuzzy-concept BuyerCarKM left-shoulder(0,100000,10000,20000))

(define-concept Pref1 (and Car (some hasPrice BuyerCarPrice)))
(define-concept Pref2 (and Car (some hasKM BuyerCarKM)))
(define-concept BuyDegree (w-sum (0.7 Pref1) (0.3 Pref2)))

# Let's show the price and KM on the optimal agreement

(show-concrete-fillers hasPrice hasKM)

#(max-sat? (and BuyDegree C455)) #degree = 0.444103, hasPrice= 11805.1 hasKM= 18000
(max-sat? (and BuyDegree C34)) #degree = 0.605634, hasPrice= 11053.5 hasKM= 17000
#(max-sat? (and BuyDegree C1812)) #degree = 0.515464, hasPrice= 11740.2 hasKM= 16000

So the better match would be car C34 and the agreement should be on $11053.5.

The example file can be found here.