ENH remove all floating node logic (not sure what I was thinking)

This commit is contained in:
Nathan Dwarshuis 2022-03-06 22:24:39 -05:00
parent 39d06d7c80
commit 77e4939a7d
1 changed files with 49 additions and 54 deletions

View File

@ -43,6 +43,37 @@ The type of WHAT will determine how the hash table is build:
((numberp what) (make-hash-table :size what :test #'equal))
(t (ht<-alist what #'equal))))
(defun dag--bimap-create (init)
"Create a bidirectional adjacency list.
INIT is an alist where the car is a child key and the cdr is the
parent keys for that child."
(let ((ht-child (dag--ht-create nil))
(ht-parent (dag--ht-create nil))
key parents)
(--each init
(setq key (car it)
parents (cdr it))
(ht-set ht-child key parents)
(ht-set ht-parent key nil))
(--each init
(setq key (car it)
parents (cdr it))
(while parents
(->> (ht-get ht-parent (car parents))
(cons key)
(ht-set ht-parent (car parents)))
(!cdr parents)))
(list :parent ht-parent :child ht-child)))
;; (defun dag--bimap-remove (keys bimap)
;; (-let (((&plist :parent :child) bimap))
;; (--each keys
;; (--each (ht-get child it)
;; (ht-set parent it (remove it it))
;; (ht-remove child it)
;; (ht-remove parent it))))))
(defun dag--plist-cons (plist prop x)
(plist-put plist prop (cons x (plist-get plist prop))))
@ -130,24 +161,6 @@ The type of WHAT will determine how the hash table is build:
(when (--all-p (= 0 it) (ht-values parent-degrees))
(nreverse ordered-nodes))))
(defun dag--get-floating (adjlist init)
;; Find 'floating nodes', which are nodes that have no children or parents
;; (this will happen if the original alist has node keys that aren't
;; referenced by any parents).
;;
;; O(N)
(let ((acc (or init (dag--ht-create nil)))
cur)
(dag--each-key adjlist
(setq cur (ht-get adjlist it))
;; If adjlist key has parents and/or children, remove it from the floating
;; if present, otherwise add it to floating and remove it from adjlist
(if (or (plist-get cur :children) (plist-get cur :parents))
(ht-remove acc it)
(ht-remove adjlist it)
(ht-set acc it t)))
(list adjlist acc)))
(defun dag--alist-to-ht (parent-adjlist)
(let ((h (dag--ht-create parent-adjlist))
(broken-edges (dag--ht-create nil))
@ -218,14 +231,10 @@ The type of WHAT will determine how the hash table is build:
(setq order (cdr order)))
extra-edges))
(defun dag--create (adjlist broken-edges floating)
;; TODO this floating this is probably not necessary; it automatically makes
;; any algorithm using this function at least O(N)
(-let (((a f) (dag--get-floating adjlist floating)))
(list :adjlist a
(defun dag--create (adjlist broken-edges)
(list :adjlist adjlist
:broken-edges broken-edges
:floating-nodes f
:order (dag--get-topological-order adjlist))))
:order (dag--get-topological-order adjlist)))
(defun dag--prune-broken-edges (broken-edges)
(dag--each-key broken-edges
@ -233,15 +242,14 @@ The type of WHAT will determine how the hash table is build:
(ht-remove broken-edges it)))
broken-edges)
(defun dag--adjlist-remove-nodes (to-remove adjlist broken-edges floating)
(defun dag--adjlist-remove-nodes (to-remove adjlist broken-edges)
(let (r r-rel child-rel)
(while to-remove
;; If the node to be removed is in the adjacency list, get a list of its
;; parents, remove the node from the child list of each parent, then
;; delete the node itself. Otherwise try to delete if from floating nodes.
;; delete the node itself.
(setq r (car to-remove))
(if (not (setq r-rel (ht-get adjlist r)))
(ht-remove floating r)
(when (setq r-rel (ht-get adjlist r))
(--each (plist-get r-rel :parents)
(when (and (not (member it to-remove)) (ht-contains-p adjlist it))
(dag--adjlist-remove-child-edge it r adjlist)))
@ -258,7 +266,7 @@ The type of WHAT will determine how the hash table is build:
;; presence in the adjacency list
(ht-remove broken-edges r)
(!cdr to-remove)))
(list adjlist broken-edges floating))
(list adjlist broken-edges))
(defmacro dag--intersection-difference (xs ys &optional zs)
"Calculate the intersection and difference of XS and YS.
@ -370,29 +378,29 @@ keys.
Return a DAG object."
(-let (((a b) (dag--alist-to-ht parent-adjlist)))
(dag--create a b nil)))
(dag--create a b)))
(defun dag-empty ()
"Return an empty DAG."
(dag--create (dag--ht-create nil) (dag--ht-create nil) nil))
(dag--create (dag--ht-create nil) (dag--ht-create nil)))
(defun dag-remove-nodes (to-remove dag)
(-let (((&plist :adjlist a :broken-edges b :floating-nodes f) dag))
(->> (dag--adjlist-remove-nodes to-remove a b f)
(-let (((&plist :adjlist a :broken-edges b) dag))
(->> (dag--adjlist-remove-nodes to-remove a b)
(apply #'dag--create))))
(defun dag-insert-nodes (to-insert dag)
(-let* (((&plist :adjlist a :broken-edges b :floating-nodes f) dag)
(-let* (((&plist :adjlist a :broken-edges b) dag)
((a* b*) (dag--adjlist-insert-nodes to-insert a b)))
(dag--create a* b* f)))
(dag--create a* b*)))
(defun dag-edit-nodes (to-remove to-insert dag)
(if (not (or to-remove to-insert)) dag
(-let* ((to-remove* (-difference to-remove (-map #'car to-insert)))
((&plist :adjlist a :broken-edges b :floating-nodes f) dag)
((a* b* f*) (dag--adjlist-remove-nodes to-remove a b f))
((&plist :adjlist a :broken-edges b) dag)
((a* b*) (dag--adjlist-remove-nodes to-remove a b))
((a** b**) (dag--adjlist-insert-nodes to-insert a* b*)))
(dag--create a** b** f*))))
(dag--create a** b**))))
(defun dag-get-adjacency-list (dag)
(plist-get dag :adjlist))
@ -400,9 +408,6 @@ Return a DAG object."
(defun dag-get-broken-edges (dag)
(plist-get dag :broken-edges))
(defun dag-get-floating-nodes (dag)
(plist-get dag :floating-nodes))
(defun dag-get-topological-order (dag)
(plist-get dag :order))
@ -415,9 +420,7 @@ Return a DAG object."
(< 0 (dag-get-length dag)))
(defun dag-is-empty-p (dag)
(= 0
(ht-size (dag-get-adjacency-list dag))
(ht-size (dag-get-floating-nodes dag))))
(= 0 (ht-size (dag-get-adjacency-list dag))))
(defun dag-get-node (key dag)
(-some-> (dag-get-adjacency-list dag)
@ -444,14 +447,6 @@ Return a DAG object."
(when ,form (!cons (cons it it-rel) acc)))
acc))
(defmacro dag-get-floating-nodes-where (dag form)
(declare (indent 1))
`(let ((it-adjlist (dag-get-floating-nodes ,dag))
acc)
(dag--each-key it-adjlist
(when ,form (!cons it acc)))
acc))
(defun dag-get-leaf-nodes (dag)
(dag-get-nodes-and-edges-where dag
(not (dag--adjlist-get-children it it-adjlist))))