Re: [htdig-dev] Re: [htdig] PERCENT returning 1% on big hits

[Joe R. J. <jj...@cl...>]

On Thu, 1 Jul 2004, Jim wrote:

> Date: Thu, 1 Jul 2004 15:45:10 -0600 (MDT)
> From: Jim <li...@yg...>
> To: Eli White <ew...@st...>
> Cc: htd...@li..., htd...@li...
> Subject: [htdig-dev] Re: [htdig] PERCENT returning 1% on big hits
> 
> On Thu, 1 Jul 2004, Eli White wrote:
> 
> > In fact, due to cross-linking of terms, some of those can have a VERY HIGH 
> > score.
> > 
> > The problem is, that at some point, it seems we passed a threshold, and for 
> > those extremely high hits, the PERCENT result is messed up.
> > 
> > It appears as if it occurs when it wants to give a score HIGHER than 100%, 
> > and ends up printing 1% instead.
> 
> Looks like a bug has crept into the handling of PERCENT. As you indicate,
> the problem is in fact tied to high scores. The score, which is stored as
> an int, is multiplied by 100 (literal), resulting in an overflow whenever
> the score is much more than 20 million. If the result ends up negative,
> percent is manually set to 1; otherwise you just get whatever garbage
> resulted from the overflow.
> 
> Based on a quick look, I think it is an easy fix. However you would need
> to touch the source and rebuild at least htsearch. My assumption is that
> if you replace the 100 with 100.0 at line 314 of htsearch/Display.cc (for
> ht://Dig 3.1.6), then you will avoid the overflow and correct the problem
> you are encountering. I haven't actually tested this. If you are able to
> test this and it solves the problem, please let us know. You might also
> consider submitting a bug report if you get a chance just to make sure
> this issue doesn't get lost in the shuffle.
> 
> Jim

I can't test your fix either, but I have put it as a patch in:

  ftp://ftp.ccsf.org/htdig-patches/3.1.6/percent.0

If it works we can fix 3.2.0b6 too:

--- htsearch/Display.cc.orig	Fri May 28 06:15:24 2004
+++ htsearch/Display.cc	Thu Jul  1 15:51:29 2004
@@ -362,7 +362,7 @@
 
     if (maxScore != 0 && maxScore != minScore)
       {
-	int percent = (int)((ref->DocScore() - minScore) * 100 /
+	int percent = (int)((ref->DocScore() - minScore) * 100.0 /
 			    (maxScore - minScore));
 	if (percent <= 0)
 	  percent = 1;

Regards,

Joe
-- 
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  _/_/ oe _/   _/.  _/_/ ah        jj...@cl...

> > Can anyone shed some light on why this is happening?  It happens with 3.1.5 
> > AND 3.1.6 ...
> > 
> > Some example star/percent/score results to peruse:
> > 
> > Search (A)
> > Result 1:  1% - 5 stars - score: 40695460
> > Result 2: 24% - 2 stars - score:  9850704
> > Result 3: 24% - 2 stars - score:  9808377
> > Result 4: 16% - 2 stars - score:  8606539
> > 
> > Search (B)
> > Result 1: 11% - 5 stars - score: 48628560
> > Result 2: 43% - 3 stars - score: 21387546
> > Result 3: 23% - 2 stars - score: 11271058
> > Result 4: 17% - 2 stars - score:  8733621
> > 
> > Search (C)
> > Result 1:  1% - 5 stars - score: 761285184
> > Result 2:  1% - 1 star  - score:  51412848
> > Result 3:  1% - 1 star  - score:  43010124
> > Result 4:  2% - 1 star  - score:  20066298
> > 
> > And so on ...
> > 
> > Thanks in advance,
> > Eli