Re: Scoring out of bounds

[Katsumi Yamaoka <yamaoka@jpl.org>]

>>>>> In <b9yekwohj9a.fsf@jpl.org> Katsumi Yamaoka wrote:

>>>>>> In <vz3cd7c6bu.fsf@redqueen.bytechase.cx>
>>>>>>	Norbert Koch <viteno@xemacs.org> wrote:

>>> Something's pushing scores up too high (my bad), but maybe it should
>>> be bound in gnus-decay-score to prevent such errors?

>> Here's a possible fix

>>  (defun gnus-decay-score (score)
>>    "Decay SCORE according to `gnus-score-decay-constant' and `gnus-score-decay-scale'."

[...]

>> +  (condition-case nil
>> +      (floor
>> +       (- score
>> +	  (* (if (< score 0) -1 1)
>> +	     (min (abs score)
>> +		  (max gnus-score-decay-constant
>> +		       (* (abs score)
>> +			  gnus-score-decay-scale))))))
>> +    (arith-error most-positive-fixnum)))

> I've committed it with a slight modification[1].  Thanks.

I noticed that solution does not decay a score value eternally,
and replaced it in CVS with the following definition:

(defun gnus-decay-score (score)
  "Decay SCORE according to `gnus-score-decay-constant' and `gnus-score-decay-scale'."
  (let ((n (- score
	      (* (if (< score 0) -1 1)
		 (min (abs score)
		      (max gnus-score-decay-constant
			   (* (abs score)
			      gnus-score-decay-scale)))))))
    (if (and (featurep 'xemacs)
	     ;; XEmacs' floor can handle only the floating point
	     ;; number below the half of the maximum integer.
	     (> (abs n) (/ (lsh -1 -2))))
	(string-to-number
	 (car (split-string (number-to-string n) "\\.")))
      (floor n))))
-- 
Katsumi Yamaoka <yamaoka@jpl.org>