ompayne
/
sicp
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Complete up to exercise 4.59

This commit is contained in:
Oliver Payne 2024-04-09 23:08:14 +01:00
parent 3978de8110
commit 6e08a14960
1 changed files with 85 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

85
mceval/logic-programming.rkt
View File

@ -28,3 +28,88 @@
(and (supervisor ?person ?supervisor)
(job ?supervisor ?supervisor-job)
(not (job ?supervisor (computer . ?x))))
;; Exercise 4.57
;; Define a rule that says that person 1 can replace person 2 if
;; either person 1 does the same job as person 2 or someone who does
;; person 1's job can also do person 2's job, and if person 1 and
;; person 2 are not the same person.
(assert! (rule (can-replace ?person-1 ?person-2)
(and (or (and (job ?person-1 ?job)
(job ?person-2 ?job))
(and (job ?person-1 ?job1)
(job ?person-2 ?job2)
(can-do-job ?job1 ?job2)))
(not (same ?person-1 ?person-2)))))
;; All people who can replace Cy D Fect
;; ;;; Query input:
;; (can-replace ?person (Fect Cy D))
;; ;;; Query results:
;; (can-replace (Bitdiddle Ben) (Fect Cy D))
;; (can-replace (Hacker Alyssa P) (Fect Cy D))
;; All people who can replace someone who is being paid more than
;; they are, together with the two salaries.
(and (can-replace ?person-1 ?person-2)
(salary ?person-1 ?salary-1)
(salary ?person-2 ?salary-2)
(lisp-value > ?salary-2 ?salary-1))
;; Not sure why results are duplicated
;; ;;; Query results:
;; (and (can-replace (Aull DeWitt) (Warbucks Oliver)) (salary (Aull DeWitt) 25000) (salary (Warbucks Oliver) 150000) (lisp-value > 150000 25000))
;; (and (can-replace (Aull DeWitt) (Warbucks Oliver)) (salary (Aull DeWitt) 25000) (salary (Warbucks Oliver) 150000) (lisp-value > 150000 25000))
;; (and (can-replace (Fect Cy D) (Hacker Alyssa P)) (salary (Fect Cy D) 35000) (salary (Hacker Alyssa P) 40000) (lisp-value > 40000 35000))
;; (and (can-replace (Fect Cy D) (Hacker Alyssa P)) (salary (Fect Cy D) 35000) (salary (Hacker Alyssa P) 40000) (lisp-value > 40000 35000))
;; Exercise 4.58 Define a rule that says that a person is a "big shot"
;; in a division if the person works in the division but does not have
;; a supervisor who works in the division.
(assert! (rule (big-shot ?person)
(and (supervisor ?person ?supervisor)
(job ?person (?person-division . ?person-job))
(job ?supervisor (?supervisor-division . ?supervisor-job))
(not (same ?person-division ?supervisor-division)))))
;; ;;; Query input:
;; (big-shot ?person)
;; ;;; Query results:
;; (big-shot (Scrooge Eben))
;; (big-shot (Bitdiddle Ben))
;; Exercise 4.59
;; Add meetings
(assert! (meeting accounting (Monday 9am)))
(assert! (meeting administration (Monday 10am)))
(assert! (meeting computer (Wednesday 3pm)))
(assert! (meeting administration (Friday 1pm)))
(assert! (meeting whole-company (Wednesday 4pm)))
;; (a) All meetings on Friday
(meeting ?group (Friday . ?time))
;; ;;; Query results:
;; (meeting administration (Friday 1pm))
;; (b) Alyssa's by-name meeting-time rule
(assert! (rule (meeting-time ?person ?day-and-time)
(and (job ?person (?group . ?job))
(and (or (meeting ?group ?day-and-time)
(meeting whole-company ?day-and-time))))))
;; (c) Alyssa's Wednesday meetings:
;; ;; Query input:
;; (meeting-time (Hacker Alyssa P) (Wednesday . ?time))
;; ;;; Query results:
;; (meeting-time (Hacker Alyssa P) (Wednesday 3pm))
;; (meeting-time (Hacker Alyssa P) (Wednesday 4pm))