On Tue, Oct 27, 2009 at 4:19 PM, Franz Lehner wrote:
ok here is a minimal example how to get remembering function.
I am however not sure if hash tables are actually used.
This example sub-classes Table to create a domain whose values are cached functions.
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(1) -> <spad>
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)abbrev domain FWC FunctionWithCache
FunctionWithCache(A:SetCategory,F:Partition->A):Exports == Implementation where
Exports ==> TableAggregate(SExpression,A) with
apply:(%,Partition)-> A
++ \spad{f(p)} computes the value of the function f
++ remembering its values
Implementation ==> Table(SExpression,A) add
Rep := Table(SExpression,A)
rep(x:%):Rep == x :: Rep
per(r:Rep):% == r :: %
part2expr:Partition -> SExpression -- should go to Partition
part2sexpr(p:Partition):SExpression ==
pl:List Integer := coerce(p)
convert( [convert(k)@SExpression for k in pl])@SExpression
apply(f:%,p:Partition):A ==
repf:Rep := rep f
import Rep
ps:SExpression := part2sexpr(p)
res:= search(ps,rep f)$Rep
res case "failed" =>
output("F called")$OutputPackage
res1:A :=F(p)
-- repf(ps) := res1 -- method 1
HPUT(rep f,ps,res1)$Lisp -- method 2 (faster?)
res1
res pretend A</spad>
fricas
Compiling FriCAS source code from file
/var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/7804888174701501931-25px001.spad
using old system compiler.
FWC abbreviates domain FunctionWithCache
------------------------------------------------------------------------
initializing NRLIB FWC for FunctionWithCache
compiling into NRLIB FWC
compiling local rep : % -> Rep
FWC;rep is replaced by x
Time: 0 SEC.
compiling local per : Rep -> %
FWC;per is replaced by r
Time: 0 SEC.
compiling local part2sexpr : Partition -> SExpression
Time: 0 SEC.
compiling exported apply : (%,Partition) -> A
Time: 0 SEC.
****** Domain: (Record (: key (SExpression)) (: entry A)) already in scope
augmenting (Record (: key (SExpression)) (: entry A)): (Evalable (Record (: key (SExpression)) (: entry A)))
****** Domain: % already in scope
augmenting %: (finiteAggregate)
****** Domain: % already in scope
augmenting %: (finiteAggregate)
****** Domain: (Record (: key (SExpression)) (: entry A)) already in scope
augmenting (Record (: key (SExpression)) (: entry A)): (OrderedSet)
****** Domain: % already in scope
augmenting %: (finiteAggregate)
****** Domain: % already in scope
augmenting %: (finiteAggregate)
****** Domain: A already in scope
augmenting A: (OrderedSet)
****** Domain: A already in scope
augmenting A: (Evalable A)
****** Domain: (Record (: key (SExpression)) (: entry A)) already in scope
augmenting (Record (: key (SExpression)) (: entry A)): (ConvertibleTo (InputForm))
****** Domain: (SExpression) already in scope
augmenting (SExpression): (OrderedSet)
****** Domain: % already in scope
augmenting %: (finiteAggregate)
(time taken in buildFunctor: 4057)
;;; *** |FunctionWithCache| REDEFINED
;;; *** |FunctionWithCache| REDEFINED
Time: 0.01 SEC.
Warnings:
[1] apply: pretendA -- should replace by @
Cumulative Statistics for Constructor FunctionWithCache
Time: 0.03 seconds
--------------non extending category----------------------
.. FunctionWithCache(#1,#2) of cat
(|Join| (|TableAggregate| (|SExpression|) |#1|)
(CATEGORY |domain| (SIGNATURE |apply| (|#1| % (|Partition|))))) has no
(|finiteAggregate|) finalizing NRLIB FWC
Processing FunctionWithCache for Browser database:
--->-->FunctionWithCache(constructor): Not documented!!!!
--------(apply (A % (Partition)))---------
--->-->FunctionWithCache(): Missing Description
; compiling file "/var/aw/var/LatexWiki/FWC.NRLIB/FWC.lsp" (written 07 DEC 2024 05:55:27 AM):
; wrote /var/aw/var/LatexWiki/FWC.NRLIB/FWC.fasl
; compilation finished in 0:00:00.016
------------------------------------------------------------------------
FunctionWithCache is now explicitly exposed in frame initial
FunctionWithCache will be automatically loaded when needed from
/var/aw/var/LatexWiki/FWC.NRLIB/FWC
How to use:
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f:FunctionWithCache(Integer,pdct):=empty()
Type: FunctionWithCache
?(Integer,
theMap(PRTITION;pdct;%I;18,
655))
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p:Partition := partition [1,1]
Type: Partition
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f(p)
F called
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f(p)