Ok, so i have this edu_less(hs,college). edu_less(college,masters). edu_less(masters,phd). I need to write a function to tell if something is than the other. The predicate is edu_le. So if i put edu_le(hs,phd). it should return yes. I came up with this. edu_le(A,B) :- A = B. edu_le(A,B) :- edu_less(A,B). edu_le(A,B) :- edu_less(A,...
Is there anything in Prolog that works like a for loop and if then condition? ...
Hi, in short: How to find min value in a list? (thanks for the advise kaarel) long story: I have created a weighted graph in amzi prolog and given 2 nodes, I am able to retrieve a list of paths. However, I need to find the minimum value in this path but am unable to traverse the list to do this. May I please seek your advise on how t...
Hello, I have a small question. I need to make a predicate that counts from a natural number to some other natural number. I have to implement a check too, that the second interval is bigger than the first one. However I got stuck during my way. Here is my code (SWI-PROLOG) count(O, _, O). count(A, B, C) :- count(A, B, D), C is D+1, C ...
Hi everyone, In short: I am trying to traverse an undirected graph in prolog, but don't know how to, any advise would be greatly appreciated. Background: Trying to model rail system, with stations as nodes and their links as edges with weight 1. I had no problem doing it in a directed manner, but cant do it in an undirected graph. ...
i am writing a predicate in prolog to delete an atom in a list, but i stuck on how to check if the atom is whether a list inside a list. any suggestions. ...
Heres a snippet: translate("a", "4"). translate("m", "/\\/\\"). tol33t([], []). tol33t([Upper|UpperTail], [Lower|LowerTail]) :- translate([Upper], [Lower]), tol33t(UpperTail, LowerTail). Basically what i want to do is look up in the table for a letter and then get that letter and add it to the new list. What i have works if ...
Hi there, I can write a predicate that is satisfied when two lists are equal e.g. equal([2,3],[2,3]) would be true and equal([2,3],[4,5]). would be false. However, what if I want to have a list and try and match it with any list in a list of lists e.g. match([2,3],[[5,6],[4,6,2],[2,3]]). would be true because of the last list in the li...
I am trying to write Prolog code to determine whether the bound variable X is in the scope of the bound variable Y in a list. Lists may be nested and X is in the scope of Y if X and Y are members of the same list or if X is a member of a list that is a member of a list that is a member of a list...(nested indefinitely) that is in the sam...
TL;DR: Need help calling a rule with a fact I´ve started out with prolog, coming from C and got stuff working... until they evidently got broken. I´m writing a small car-paint program for myself as I´m learning this new language Im trying to call a rule with a fact (is this possible?), what I want to do is use one fact "cars" and anothe...
Hi. I have a problem where I have a list like this: [[el1, el2, el3], [el4, el5, el6], [[el7, el8, el9], [el10, el11, el12], ..... , [elxx, elyy, elzz]], [el, el, el]...]] I want to pattern match the inner list of lists, the [el7, el8, el9], [el10, el11, el12], ..... , [elxx, elyy, elzz] How can this be done? As of now I pattern...
So , i still don't completely understand how lists and recursion work in prolog, could be why i am having trouble with this, but i don't even know how to begin this problem. There is a list of friends. f(a,b). f(a,c). f(a,d). f(b,c). f(b,e). f(b,f). f(c,e). f(c,g). f(g,e). etc.. I have to find if someone is a friend through someone e...
I need to build a new list with a "loop". Basically i can't use recursion explicitly, so i am using append to go through lists of list. I can get the element. Problem is i need to check this element and if something is true it returns another element i need to put back into the list. It does check correctly and it changes correctly. Pr...
Ok, here's the deal: I've got two piles of shirts I want to take a random shirt from each pile and put them in a new pile Then get the new pile out And here is the code: mix([],[],_). mix(P1,P2, Pile):- takeshirt(P1,1,Taken1,Rem1), takeshirt(P2,1,Taken2,Rem2), #Take one append(Pile,Taken1,New), append(New,Taken2,New...
Hi. I am trying to call a prolog program and receive output into my bash script. Currently I am using the extremely crude version of using halt(0) or halt(1) and then examining the exit code in bash, using 0 as true and 1 as false to the question my prolog program answers. Is there a better way to handle output? I am using gnu prolog. I...
Hello Guys Please forgive me if this is the wrong place for asking this question. Kindly point me to the right place. Thanks. I am learning prolog and need help finding a good book that can help me understand it so that i can do all my assigments. At the moment i have LEARN PROLOG NOW from Blackburn but it seems i still miss some thing...
If I have defined all the digits in a prolog database, such as dig(0),dig(1)...dig(9), what query can I use for prolog to return the largest digit, so 9? I tried something like dig(N),dig(M),N>M, but that just returns the first possibility, not the largest number. ...
I have a large number of facts within my program, listing developers and designers in a company, as well as previous projects, like so.. % project(Project Name,Year) project(efnet, 2007). % designer(Project Name, Name, Role) designer(efnet, jane_cole, lead). % developer(Project Name, Name, Role) developer(efnet, alex_tobbs, architect). ...
I've got a list consisting of smaller lists inside of it, each list consisting of 2 items: [[a,1],[b,2],[c,3]] I'm using a function called take(1,L,R) to take the first item from list L and return the item R. The code for the take function is here: take(0,X,X). take(N,[H|T],[H|R]):- N>0, M is N-1, take(M,T,R). At t...