diff options
Diffstat (limited to 'gnosis-algorithm.el')
| -rw-r--r-- | gnosis-algorithm.el | 79 |
1 files changed, 16 insertions, 63 deletions
diff --git a/gnosis-algorithm.el b/gnosis-algorithm.el index 9b3ebb3..64c08c3 100644 --- a/gnosis-algorithm.el +++ b/gnosis-algorithm.el @@ -133,69 +133,22 @@ value (second item) by DECREASE." (setf new-ef (gnosis-algorithm-replace-at-index 1 (+ (nth 1 ef) decrease) new-ef))))) (gnosis-algorithm-round-items new-ef))) -(defun gnosis-algorithm-e-factor (ef success) - "Calculate the new e-factor given existing EF and SUCCESS, either t or nil." - (pcase success - (`t (+ ef (car gnosis-algorithm-ef))) - (`nil (max 1.3 (- ef (cadr gnosis-algorithm-ef)))))) - - -(cl-defun gnosis-algorithm-next-interval (&key last-interval review-num ef success failure-factor successful-reviews successful-reviews-c fails-c fails-t initial-interval) - "Calculate next interval. -- LAST-INTERVAL : The number of days since the item was last reviewed. --review-num: Number of times the item has been reviewed. -- EF : Easiness Factor. -- SUCCESS : Success of the recall, ranges from 0 (unsuccessful) to 1 - (successful). -- FF: Failure factor -- SUCCESSFUL-REVIEWS : Number of successful reviews. -- SUCCESSFULL-REVIEWS-C: Successful reviews in a row. -- FAILS-C: Failed reviews in a row. -- FAILS-T: Total failed reviews. -- INITIAL-INTERVAL: Initial intervals for successful reviews. - -Returns a list of: (INTERVAL N EF) where, -- Next review date in (yyyy mm dd) format. -- REVIEW-NUM: Incremented by 1. -- EF : Modified based on the recall success for the item." - ;; Check if gnosis-algorithm-ff is lower than 1 & is total-ef above 1.3 - (cond ((>= gnosis-algorithm-ff 1) - (error "Value of `gnosis-algorithm-ff' must be lower than 1")) - ((< (nth 2 gnosis-algorithm-ef) 1.3) - (error "Value of total-ef from `gnosis-algorithm-ef' must be above 1.3"))) - ;; Calculate the next easiness factor. - (let* ((next-ef (gnosis-algorithm-e-factor ef success)) - (interval - (cond - ;; TODO: Rewrite this! - ;; First successful review -> first interval - ((and (= successful-reviews 0) success - (car initial-interval))) - ;; Second successful review -> second interval - ((and (= successful-reviews 1) success) - (cadr initial-interval)) - ;; When successful-reviews-c is above 3, use 150% or 180% - ;; of ef depending on the value of successful-reviews - ((and success - (>= successful-reviews-c 3) - (>= review-num 5) - (> last-interval 1)) - (* (* ef (if (>= successful-reviews 10) 1.8 1.5)) last-interval)) - ((and (equal success nil) - (> fails-c 3) - (>= review-num 5) - (> last-interval 1)) - ;; When fails-c is above 3, use 150% or 180% of - ;; failure-factor depending on the value of total failed - ;; reviews. - (* (max (min 0.8 (* failure-factor (if (>= fails-t 10) 1.8 1.5))) - failure-factor) - last-interval)) - ;; For everything else - (t (if success - (* ef last-interval) - (* failure-factor last-interval)))))) - (list (gnosis-algorithm-date (round interval)) next-ef))) +(cl-defun gnosis-algorithm-next-interval (&key last-interval ef success successful-reviews + failure-factor initial-interval) + "Calculate next interval." + (cl-assert (< gnosis-algorithm-ff 1) "Value of `gnosis-algorithm-ff' must be lower than 1") + ;; This should only occur in testing env or when the user has made breaking changes. + (cl-assert (> (nth 2 ef) 1) "Total ef value must be above 1") + (let* ((ef (nth 2 gnosis-algorithm-ef)) + (interval (cond ((and (= successful-reviews 0) success) + (car initial-interval)) + ((and (= successful-reviews 1) success) + (cadr initial-interval)) + (t (if success + (* ef last-interval) + (* failure-factor last-interval)))))) + (gnosis-algorithm-date (round interval)))) + (provide 'gnosis-algorithm) ;;; gnosis-algorithm.el ends here |