Some small improvements. while on the bus

This commit is contained in:
Hugo Sales 2018-11-17 22:28:51 +00:00
parent 66dfb6084c
commit 43340345d6
2 changed files with 89 additions and 26 deletions

3
.gitignore vendored Normal file
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@ -0,0 +1,3 @@
*#*
.#*
*~

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@ -10,45 +10,105 @@ power_p(X) :-
power_p(X^N) :-
polynomial_variable_p(X), integer(N), N > 1, !.
coefficient_p(K) :-
number(K).
%% coefficient_p(K) :-
%% number(K).
%% monomial_p(X) :-
%% term_p(X) :-
%% polynomial_variable_p(X), !.
monomial_p(N) :-
number(N), !.
monomial_p(X) :-
power_p(X), !.
monomial_p(K * X) :-
coefficient_p(K),
power_p(X), !.
term_p(N) :-
number(N).
term_p(X) :-
power_p(X).
term_p(L * R) :-
term_p(L),
term_p(R), !.
polynomial_p(M) :-
monomial_p(M), !.
polynomial_p(P + M) :-
monomial_p(M),
polynomial_p(P), !.
term_p(M).
polynomial_p(L + R) :- % Left greedy
polynomial_p(L), !, % Why?
term_p(R), !.
simplify_monomial(1 * P, P) :-
power_p(P), !.
simplify_monomial(0 * _, 0) :-
%% ?- polynomial_p(3*x^2+y*z).
%@ true.
%% ?- polynomial_p(x^100*y*z).
%@ true.
%% ?- polynomial_p(x+y+z).
%@ true.
%@ false.
%@ false.
%% ?- polynomial_p(3*x^2+y*z+x^100*y*z).
%@ true.
%@ true .
%@ false.
%@ false.
%@ false.
%@ false.
simplify_term(1 * P, P) :-
term_p(P), !.
simplify_term(0 * _, 0) :-
!.
simplify_monomial(M, M).
simplify_term(T, S) :-
term_to_list(T, L),
sort(L, L2),
join_like_terms(L2, S).
%% ?- simplify_term(2*y*z*x^3*x, X).
%@ X = [2, x^1, x^3, y^1, z^1].
join_like_terms([T1, T2 | L], [P^N | L]) :-
P^N1 is T,
P^N2 is T2,
N is N1 + N2,
!.
join_like_terms([N1, N2 | L], [N | L]) :-
N is N1 * N2,
!.
join_like_terms(T, T).
%% ?- join_like_terms([2, 3, x^1, x^2], T).
%@ ERROR: Arguments are not sufficiently instantiated
%@ ERROR: In:
%@ ERROR: [9] _3138^_3140 is _3134
%@ ERROR: [8] join_like_terms([2,3|...],[_3188^_3190,...|...]) at /tmp/ediprologODLYxF:62
%@ ERROR: [7] <user>
%@ Exception: (8) join_like_terms([2, 3, x^1, x^2], _2428) ? abort
%@ % Execution Aborted
%@ T = [6, x^1, x^2].
%@ T = [6, x^1].
%@ T = [6].
%@ T = [2].
term_to_list(L * N, [N | TS]) :-
number(N),
term_to_list(L, TS), !.
term_to_list(L * T, [T2 | TS]) :-
power_p(T),
power_to_canon(T, T2),
term_to_list(L, TS), !.
term_to_list(T, [T]).
power_to_canon(T, T^1) :-
polynomial_variable_p(T).
power_to_canon(T^N, T^N) :-
polynomial_variable_p(T).
simplify_polynomial(M, M2) :-
monomial_p(M), simplify_monomial(M, M2), !.
term_p(M), simplify_term(M, M2), !.
simplify_polynomial(P + 0, P) :-
monomial_p(P), !.
term_p(P), !.
simplify_polynomial(0 + P, P) :-
monomial_p(P), !.
term_p(P), !.
simplify_polynomial(P + M, P2 + M2) :-
simplify_polynomial(P, P2), simplify_monomial(M, M2).
simplify_polynomial(P, P2), simplify_term(M, M2).
simplify_polynomial(P + M, P2 + M3) :-
monomial_parts(M, _, XExp),
delete_monomial(P, XExp, M2, P2), !,
add_monomial(M, M2, M3).
simplify_polynomial(P + M, P2 + M2) :-
simplify_polynomial(P, P2), simplify_monomial(M, M2).
simplify_polynomial(P, P2), simplify_term(M, M2).
%% ?- simplify_polynomial(1*x+(-1)*x, P).
@ -63,13 +123,13 @@ monomial_parts(K, K, indep) :-
delete_monomial(M, X, M, 0) :-
monomial_p(M),
term_p(M),
monomial_parts(M, _, X), !.
delete_monomial(M + M2, X, M, M2) :-
monomial_p(M2), monomial_p(M),
term_p(M2), term_p(M),
monomial_parts(M, _, X), !.
delete_monomial(P + M, X, M, P) :-
monomial_p(M), monomial_parts(M, _, X), !.
term_p(M), monomial_parts(M, _, X), !.
delete_monomial(P + M2, X, M, P2 + M2) :-
delete_monomial(P, X, M, P2).