From 558c9053931816629594d537c770cb1100ab99a9 Mon Sep 17 00:00:00 2001 From: Matthew Butterick Date: Mon, 22 Oct 2018 22:38:14 -0700 Subject: [PATCH] yes --- csp/csp/hacs-map.rkt | 1 - csp/csp/hacs.rkt | 184 +++++++++++++++++++++---------------------- 2 files changed, 90 insertions(+), 95 deletions(-) diff --git a/csp/csp/hacs-map.rkt b/csp/csp/hacs-map.rkt index 601f397b..69c3417b 100644 --- a/csp/csp/hacs-map.rkt +++ b/csp/csp/hacs-map.rkt @@ -2,7 +2,6 @@ (require "hacs.rkt" sugar/debug) (module+ test (require rackunit)) - (define (map-coloring-csp colors neighbors) (define names (remove-duplicates (flatten neighbors) eq?)) (define vds (for/list ([name (in-list names)]) diff --git a/csp/csp/hacs.rkt b/csp/csp/hacs.rkt index 8ce556e3..d5a10afb 100644 --- a/csp/csp/hacs.rkt +++ b/csp/csp/hacs.rkt @@ -15,8 +15,8 @@ (let loop ([argss argss][acc empty]) (if (null? argss) (yield (reverse acc)) - (for ([arg (in-list (car argss))]) - (loop (cdr argss) (cons arg acc)))))))) + (for ([arg (car argss)]) + (loop (cdr argss) (cons arg acc)))))))) (struct csp (vars constraints [assignments #:auto] [checks #:auto]) #:mutable #:transparent #:auto-value 0) @@ -33,7 +33,7 @@ (raise-argument-error 'constraint-proc "csp" prob)) ;; apply proc in many-to-many style (for/and ([args (in-cartesian (map (λ (name) (find-domain prob name)) (constraint-names const)))]) - (apply (constraint-proc const) args)))) + (apply (constraint-proc const) args)))) (define name? symbol?) @@ -74,15 +74,15 @@ ((csp? (or/c (listof name?) procedure?)) ((or/c (listof any/c) procedure?)) . ->* . void?) (for/fold ([vrs (vars prob)] #:result (set-csp-vars! prob vrs)) - ([name (in-list (if (procedure? names-or-procedure) - (names-or-procedure) - names-or-procedure))]) + ([name (in-list (match names-or-procedure + [(? procedure? proc) (proc)] + [names names]))]) (when (memq name (map var-name vrs)) (raise-argument-error 'add-vars! "var that doesn't already exist" name)) (append vrs (list (var name - (if (procedure? vals-or-procedure) - (vals-or-procedure) - vals-or-procedure)))))) + (if (procedure? vals-or-procedure) + (vals-or-procedure) + vals-or-procedure)))))) (define/contract (add-var! prob name [vals-or-procedure empty]) ((csp? name?) ((or/c (listof any/c) procedure?)) . ->* . void?) @@ -92,11 +92,11 @@ ((csp? procedure? (listof (listof name?))) ((or/c #false name?)) . ->* . void?) (set-csp-constraints! prob (append (constraints prob) (for/list ([names (in-list namess)]) - (for ([name (in-list names)]) - (check-name-in-csp! 'add-constraints! prob name)) - (make-constraint names (if proc-name - (procedure-rename proc proc-name) - proc)))))) + (for ([name (in-list names)]) + (check-name-in-csp! 'add-constraints! prob name)) + (make-constraint names (if proc-name + (procedure-rename proc proc-name) + proc)))))) (define/contract (add-pairwise-constraint! prob proc var-names [proc-name #false]) ((csp? procedure? (listof name?)) (name?) . ->* . void?) @@ -132,7 +132,7 @@ (check-name-in-csp! 'find-var prob name) (for/first ([vr (in-vars prob)] #:when (eq? name (var-name vr))) - vr)) + vr)) (define/contract (find-domain prob name) (csp? name? . -> . (listof any/c)) @@ -145,7 +145,7 @@ (csp? name? . -> . any/c) (for/or ([vr (in-vars prob)] #:when (assigned-var? vr)) - (eq? name (var-name vr)))) + (eq? name (var-name vr)))) (define/contract (reduce-function-arity proc pattern) (procedure? (listof any/c) . -> . procedure?) @@ -177,20 +177,20 @@ (ormap assigned? (constraint-names constraint))) (make-csp (vars prob) (for/list ([const (in-constraints prob)]) - (cond - ;; no point reducing 2-arity functions because they will be consumed by forward checking - [(and (or (not minimum-arity) (<= minimum-arity (constraint-arity const))) - (partially-assigned? const)) - (match-define (constraint cnames proc) const) - ;; pattern is mix of values and boxed symbols (indicating variables to persist) - ;; use boxes here as cheap way to distinguish id symbols from value symbols - (define reduce-arity-pattern (for/list ([cname (in-list cnames)]) - (if (assigned? cname) - (first (find-domain prob cname)) - (box cname)))) - (constraint (filter-not assigned? cnames) - (reduce-function-arity proc reduce-arity-pattern))] - [else const])))) + (cond + ;; no point reducing 2-arity functions because they will be consumed by forward checking + [(and (or (not minimum-arity) (<= minimum-arity (constraint-arity const))) + (partially-assigned? const)) + (match-define (constraint cnames proc) const) + ;; pattern is mix of values and boxed symbols (indicating variables to persist) + ;; use boxes here as cheap way to distinguish id symbols from value symbols + (define reduce-arity-pattern (for/list ([cname (in-list cnames)]) + (if (assigned? cname) + (first (find-domain prob cname)) + (box cname)))) + (constraint (filter-not assigned? cnames) + (reduce-function-arity proc reduce-arity-pattern))] + [else const])))) (define nassns 0) @@ -200,14 +200,18 @@ (define (reset-nfcs!) (set! nfchecks 0)) +(define nchecks 0) + +(define (reset-nchecks!) (set! nchecks 0)) + (define/contract (assign-val prob name val) (csp? name? any/c . -> . csp?) (when-debug (set! nassns (add1 nassns))) (make-csp - (for/list ([vr (vars prob)]) - (if (eq? name (var-name vr)) - (assigned-var name (list val)) - vr)) + (for/list ([vr (in-vars prob)]) + (if (eq? name (var-name vr)) + (assigned-var name (list val)) + vr)) (constraints prob))) (define/contract (unassigned-vars prob) @@ -232,7 +236,7 @@ (csp? var? . -> . natural?) (for/sum ([const (in-constraints prob)] #:when (memq (var-name var) (constraint-names const))) - 1)) + 1)) (define/contract (domain-length var) (var? . -> . natural?) @@ -255,7 +259,7 @@ (random-pick (for/list ([uv (in-list mrv-uvars)] [degree (in-list degrees)] #:when (= max-degree degree)) - uv))])])) + uv))])])) (define first-domain-value values) @@ -267,8 +271,8 @@ [cnames (in-value (constraint-names const))] #:when (and (= (length names) (length cnames)) (for/and ([name (in-list names)]) - (memq name cnames)))) - const)) + (memq name cnames)))) + const)) (define (two-arity? const) (= 2 (constraint-arity const))) @@ -278,33 +282,33 @@ (define/contract (forward-check prob ref-name) (csp? name? . -> . csp?) (define aval (first (find-domain prob ref-name))) - (define (check-var v) - (match v + (define (check-var vr) + (match vr ;; don't check against assigned vars, or the reference var ;; (which is probably assigned but maybe not) - [(? (λ (x) (or (assigned-var? x) (eq? (var-name x) ref-name)))) v] + [(? (λ (x) (or (assigned-var? x) (eq? (var-name x) ref-name)))) vr] [(var name vals) (match ((constraints prob) . relating-only . (list ref-name name)) - [(? empty?) v] + [(? empty?) vr] [constraints (define new-vals (for/list ([val (in-list vals)] #:when (for/and ([const (in-list constraints)]) - (let ([proc (constraint-proc const)]) - (if (eq? name (first (constraint-names const))) - (proc val aval) - (proc aval val))))) - val)) - (checked-variable name new-vals (cons ref-name (match v + (let ([proc (constraint-proc const)]) + (if (eq? name (first (constraint-names const))) + (proc val aval) + (proc aval val))))) + val)) + (checked-variable name new-vals (cons ref-name (match vr [(checked-variable _ _ history) history] [else null])))])])) (define checked-vars (map check-var (vars prob))) (when-debug (set! nfchecks (+ (length checked-vars) nchecks))) ;; conflict-set will be empty if there are no empty domains (as we would hope) - (define conflict-set (for*/list ([cv (in-list checked-vars)] - #:when (empty? (domain cv)) - [name (in-list (history cv))]) - name)) + (define conflict-set (for*/list ([cvr (in-list checked-vars)] + #:when (empty? (domain cvr)) + [name (in-list (history cvr))]) + name)) ;; for conflict-directed backjumping it's essential to forward-check ALL vars ;; (even after an empty domain is generated) and combine their conflicts ;; so we can discover the *most recent past var* that could be the culprit. @@ -320,7 +324,7 @@ (constraint-relates? const ref-name) (let ([other-name (first (remq ref-name (constraint-names const)))]) (singleton-var? (find-var prob other-name))))) - const)) + const)) (make-csp checked-vars nonsingleton-constraints)) (define/contract (constraint-checkable? const names) @@ -328,7 +332,7 @@ ;; constraint is checkable if all constraint names ;; are in target list of names. (for/and ([cname (in-list (constraint-names const))]) - (memq cname names))) + (memq cname names))) (define/contract (constraint-arity const) (constraint? . -> . natural?) @@ -337,8 +341,6 @@ (define (singleton-var? var) (= 1 (domain-length var))) -(define nchecks 0) -(define (reset-nchecks!) (set! nchecks 0)) (define/contract (check-constraints prob [mandatory-names #f] #:conflicts [conflict-count? #f]) ((csp?) ((listof name?) #:conflicts boolean?) . ->* . (or/c csp? natural?)) ;; this time, we're not limited to assigned variables @@ -346,26 +348,26 @@ ;; we also want to use "singleton" vars (that is, vars that have been reduced to a single domain value by forward checking) (define singleton-varnames (for/list ([vr (in-vars prob)] #:when (singleton-var? vr)) - (var-name vr))) + (var-name vr))) (define-values (checkable-consts other-consts) (partition (λ (const) (and (constraint-checkable? const singleton-varnames) (or (not mandatory-names) (for/and ([name (in-list mandatory-names)]) - (constraint-relates? const name))))) + (constraint-relates? const name))))) (constraints prob))) (cond [conflict-count? (define conflict-count (for/sum ([constraint (in-list checkable-consts)] #:unless (constraint prob)) - 1)) + 1)) (when-debug (set! nchecks (+ conflict-count nchecks))) conflict-count] [else (for ([(constraint idx) (in-indexed checkable-consts)] #:unless (constraint prob)) - (when-debug (set! nchecks (+ (add1 idx) nchecks))) - (backtrack!)) + (when-debug (set! nchecks (+ (add1 idx) nchecks))) + (backtrack!)) ;; discard checked constraints, since they have no further reason to live (make-csp (vars prob) other-consts)])) @@ -374,15 +376,15 @@ ;; todo: why does this function slow down searches? (make-csp (for/list ([vr (in-vars prob)]) - (match-define (var name vals) vr) - (define procs (for*/list ([const (in-constraints prob)] - [cnames (in-value (constraint-names const))] - #:when (and (= 1 (length cnames)) (eq? name (car cnames)))) - (constraint-proc const))) - (var name - (for*/fold ([vals vals]) - ([proc (in-list procs)]) - (filter proc vals)))) + (match-define (var name vals) vr) + (define procs (for*/list ([const (in-constraints prob)] + [cnames (in-value (constraint-names const))] + #:when (and (= 1 (length cnames)) (eq? name (car cnames)))) + (constraint-proc const))) + (var name + (for*/fold ([vals vals]) + ([proc (in-list procs)]) + (filter proc vals)))) (constraints prob))) (define/contract (backtracking-solver @@ -441,9 +443,9 @@ ((csp?) (integer?) . ->* . generator?) (generator () (for ([thread-count (or (current-thread-count) 1)]) ; todo: what is ideal thread count? - (make-min-conflcts-thread prob thread-count max-steps)) + (make-min-conflcts-thread prob thread-count max-steps)) (for ([i (in-naturals)]) - (yield (thread-receive))))) + (yield (thread-receive))))) (define/contract (optimal-stop-min proc xs) (procedure? (listof any/c) . -> . any/c) @@ -451,7 +453,7 @@ (define threshold (argmin proc sample)) (or (for/first ([candidate (in-list candidates)] #:when (<= (proc candidate) threshold)) - candidate) + candidate) (last candidates))) (define/contract (conflicted-variable-names prob) @@ -459,7 +461,7 @@ ;; Return a list of variables in current assignment that are conflicted (for/list ([name (in-variable-names prob)] #:when (positive? (nconflicts prob name))) - name)) + name)) (define/contract (min-conflicts-value prob name vals) (csp? name? (listof any/c) . -> . any/c) @@ -468,7 +470,7 @@ #:cache-keys? #true)) (for/first ([val (in-list vals-by-conflict)] #:unless (equal? val (first (find-domain prob name)))) ;; but change the value - val)) + val)) (define no-value-sig (gensym)) @@ -482,8 +484,8 @@ (define/contract (csp->assocs prob) (csp? . -> . (listof (cons/c name? any/c))) (for/list ([vr (in-vars prob)]) - (match vr - [(var name (list val)) (cons name val)]))) + (match vr + [(var name (list val)) (cons name val)]))) (define/contract (combine-csps probs) ((listof csp?) . -> . csp?) @@ -491,28 +493,17 @@ (apply append (map vars probs)) (apply append (map csp-constraints probs)))) -(define/contract (make-cartesian-generator solgens) - ((listof generator?) . -> . generator?) - (generator () - (define solstreams (for/list ([solgen (in-list solgens)]) - (for/stream ([sol (in-producer solgen (void))]) - sol))) - (let loop ([solstreams solstreams][sols empty]) - (if (null? solstreams) - (yield (combine-csps (reverse sols))) - (for ([sol (in-stream (car solstreams))]) - (loop (cdr solstreams) (cons sol sols))))))) (define/contract (extract-subcsp prob names) (csp? (listof name?) . -> . csp?) (make-csp (for/list ([vr (in-vars prob)] #:when (memq (var-name vr) names)) - vr) + vr) (for/list ([const (in-constraints prob)] #:when (for/and ([cname (in-list (constraint-names const))]) - (memq cname names))) - const))) + (memq cname names))) + const))) (define/contract (solve* prob #:finish-proc [finish-proc csp->assocs] @@ -525,12 +516,17 @@ (define subcsps ; decompose into independent csps. `cc` determines "connected components" (if (current-decompose) (for/list ([nodeset (in-list (cc (csp->graph prob)))]) - (extract-subcsp prob nodeset)) + (extract-subcsp prob nodeset)) (list prob))) + + (define solgens (map solver subcsps)) + (define solstreams (for/list ([solgen (in-list solgens)]) + (for/stream ([sol (in-producer solgen (void))]) + sol))) - (for/list ([solution (in-producer (make-cartesian-generator (map solver subcsps)) (void))] + (for/list ([solution-pieces (in-cartesian solstreams)] [idx (in-range max-solutions)]) - (finish-proc solution))) + (finish-proc (combine-csps solution-pieces)))) (define/contract (solve prob #:finish-proc [finish-proc csp->assocs]