clarify min-entry vs. min-value

main
Matthew Butterick 10 years ago
parent 899e3109d9
commit ef99bd4b2e

@ -3,7 +3,7 @@
(require racket/list sugar/debug racket/function racket/vector "logger-typed.rkt")
(define-logger ocm)
(provide smawky? Entry->Value-Type Value-Type No-Value-Type Index-Type Matrix-Proc-Type make-ocm reduce reduce2 concave-minima (prefix-out ocm- (combine-out min-value min-index)))
(provide smawky? Entry->Value-Type Value-Type No-Value-Type Index-Type Matrix-Proc-Type make-ocm reduce reduce2 concave-minima (prefix-out ocm- (combine-out min-entry min-value min-index)))
(: select-elements ((Listof Any) (Listof Index-Type) . -> . (Listof Any)))
(define (select-elements xs is)
@ -34,7 +34,7 @@
((inst vector-append Any) xs (vector value)))
(define-syntax-rule (vector-append-value xs value)
((inst vector-append Value-Type) xs (vector value)))
((inst vector-append Entry-Type) xs (vector value)))
(define-syntax-rule (vector-append-index xs value)
((inst vector-append (U Index-Type No-Value-Type)) xs (vector value)))
@ -194,28 +194,33 @@
(hash-set! hashtable key value))
(define-type Index-Type Nonnegative-Integer)
(define-type Entry-Type Any)
(define-type Value-Type Flonum)
(define-type Initial-Value-Type Value-Type)
(define-type No-Value-Type Symbol)
(define-type Finished-Value-Type Index-Type)
(define-type Matrix-Proc-Type (Index-Type Index-Type . -> . Value-Type))
(define-type Entry->Value-Type (Any . -> . Value-Type))
(define-type Entry->Value-Type (Entry-Type . -> . Value-Type))
(struct $ocm ([min-values : (Vectorof Value-Type)] [min-row-indices : (Vectorof (U Index-Type No-Value-Type))] [finished : Finished-Value-Type] [matrix-proc : Matrix-Proc-Type] [entry->value : Entry->Value-Type] [base : Index-Type] [tentative : Index-Type]) #:transparent #:mutable)
(struct $ocm ([min-entrys : (Vectorof Entry-Type)] [min-row-indices : (Vectorof (U Index-Type No-Value-Type))] [finished : Finished-Value-Type] [matrix-proc : Matrix-Proc-Type] [entry->value : Entry->Value-Type] [base : Index-Type] [tentative : Index-Type]) #:transparent #:mutable)
(define-type OCM-Type $ocm)
(: make-ocm ((Matrix-Proc-Type Entry->Value-Type) (Initial-Value-Type) . ->* . OCM-Type))
(define (make-ocm matrix-proc entry->value [initial-value 0.0])
(: make-ocm ((Matrix-Proc-Type Entry->Value-Type) (Entry-Type) . ->* . OCM-Type))
(define (make-ocm matrix-proc entry->value [initial-entry 0.0])
(log-ocm-debug "making new ocm")
($ocm (vector initial-value) (vector no-value) 0 matrix-proc entry->value 0 0))
($ocm (vector initial-entry) (vector no-value) 0 matrix-proc entry->value 0 0))
;; Return min { Matrix(i,j) | i < j }.
(: min-value (OCM-Type Index-Type . -> . Any))
(define (min-value ocm j)
(: min-entry (OCM-Type Index-Type . -> . Entry-Type))
(define (min-entry ocm j)
(if (< (cast ($ocm-finished ocm) Real) j)
(begin (advance! ocm) (min-value ocm j))
(vector-ref ($ocm-min-values ocm) j)))
(begin (advance! ocm) (min-entry ocm j))
(vector-ref ($ocm-min-entrys ocm) j)))
;; same as min-entry, but converts to raw value
(: min-value (OCM-Type Index-Type . -> . Value-Type))
(define (min-value ocm j)
(($ocm-entry->value ocm) (min-entry ocm j)))
;; Return argmin { Matrix(i,j) | i < j }.
(: min-index (OCM-Type Index-Type . -> . (U Index-Type No-Value-Type)))
@ -242,11 +247,11 @@
(for ([col (in-vector cols)])
(cond
[(>= col (vector-length ($ocm-min-values ocm)))
(set-$ocm-min-values! ocm (vector-append-value ($ocm-min-values ocm) (@ (cast (@ minima col) (HashTable Symbol Value-Type)) 'value)))
[(>= col (vector-length ($ocm-min-entrys ocm)))
(set-$ocm-min-entrys! ocm (vector-append-value ($ocm-min-entrys ocm) (@ (cast (@ minima col) (HashTable Symbol Value-Type)) 'value)))
(set-$ocm-min-row-indices! ocm (vector-append-index ($ocm-min-row-indices ocm) (@ (cast (@ minima col) (HashTable Symbol Index-Type)) 'row-idx)))]
[(< (($ocm-entry->value ocm) (@ (cast (@ minima col) HashTableTop) 'value)) (($ocm-entry->value ocm) (vector-ref ($ocm-min-values ocm) col)))
(set-$ocm-min-values! ocm ((inst vector-set Value-Type) ($ocm-min-values ocm) col (cast (@ (cast (@ minima col) HashTableTop) 'value) Value-Type)))
[(< (($ocm-entry->value ocm) (@ (cast (@ minima col) HashTableTop) 'value)) (($ocm-entry->value ocm) (vector-ref ($ocm-min-entrys ocm) col)))
(set-$ocm-min-entrys! ocm ((inst vector-set Entry-Type) ($ocm-min-entrys ocm) col (cast (@ (cast (@ minima col) HashTableTop) 'value) Value-Type)))
(set-$ocm-min-row-indices! ocm ((inst vector-set (U Index-Type No-Value-Type)) ($ocm-min-row-indices ocm) col (cast (@ (cast (@ minima col) HashTableTop) 'row-idx) Index-Type)))]))
(set-$ocm-finished! ocm next)]
@ -259,9 +264,9 @@
;; amortized against the increase in base.
(define diag (($ocm-matrix-proc ocm) (sub1 next) next))
(cond
[(< (($ocm-entry->value ocm) diag) (($ocm-entry->value ocm) (vector-ref ($ocm-min-values ocm) next)))
[(< (($ocm-entry->value ocm) diag) (($ocm-entry->value ocm) (vector-ref ($ocm-min-entrys ocm) next)))
(log-ocm-debug "advance: second case because column minimum is on the diagonal")
(set-$ocm-min-values! ocm (vector-set ($ocm-min-values ocm) next diag))
(set-$ocm-min-entrys! ocm (vector-set ($ocm-min-entrys ocm) next diag))
(set-$ocm-min-row-indices! ocm (vector-set ($ocm-min-row-indices ocm) next (sub1 next)))
(set-$ocm-base! ocm (sub1 next))
(set-$ocm-tentative! ocm next)
@ -271,7 +276,7 @@
;; any column up to tentative. We simply advance finished
;; while maintaining the invariant.
[(>= (($ocm-entry->value ocm) (($ocm-matrix-proc ocm) (sub1 next) ($ocm-tentative ocm)))
(($ocm-entry->value ocm) (vector-ref ($ocm-min-values ocm) ($ocm-tentative ocm))))
(($ocm-entry->value ocm) (vector-ref ($ocm-min-entrys ocm) ($ocm-tentative ocm))))
(log-ocm-debug "advance: third case because row i-1 does not suppply a column minimum")
(set-$ocm-finished! ocm next)]
@ -289,7 +294,7 @@
(: print (OCM-Type . -> . Void))
(define (print ocm)
(displayln ($ocm-min-values ocm))
(displayln ($ocm-min-entrys ocm))
(displayln ($ocm-min-row-indices ocm)))

Loading…
Cancel
Save