Are you sure that double precision in the RTree is necessary for your purposes?

Here is a table of floating point precision at various values:

The 'flip' values are the 'org' values with the lowest bit flipped.

             org             flip (    delta)
            0.01             0.01 ( 0.000000) (lowest bit is 10 ^ -9.030900)
            0.10             0.10 ( 0.000000) (lowest bit is 10 ^ -8.127810)
            1.00             1.00 ( 0.000000) (lowest bit is 10 ^ -7.224720)
           10.00            10.00 ( 0.000001) (lowest bit is 10 ^ -6.020600)
          100.00           100.00 ( 0.000008) (lowest bit is 10 ^ -5.117510)
         1000.00          1000.00 ( 0.000061) (lowest bit is 10 ^ -4.214420)
        10000.00         10000.00 ( 0.000977) (lowest bit is 10 ^ -3.010300)
        99999.99         99999.98 ( 0.007813) (lowest bit is 10 ^ -2.107210)
       999999.94        999999.88 ( 0.062500) (lowest bit is 10 ^ -1.204120)
      9999999.00       9999998.00 ( 1.000000) (lowest bit is 10 ^ 0.000000)
     99999992.00      99999984.00 ( 8.000000) (lowest bit is 10 ^ 0.903090)
    999999936.00     999999872.00 (64.000000) (lowest bit is 10 ^ 1.806180)


-----Original Message-----
From: sqlite-users-boun...@sqlite.org [mailto:sqlite-users-boun...@sqlite.org] 
On Behalf Of Black, Michael (IS)
Sent: 04 November 2010 02:51 PM
To: General Discussion of SQLite Database
Subject: Re: [sqlite] R*Tree module and double precision?

I'll send the patched C file to your email address.  I think the 1M patched 
version is a bit much for the email list.
 
Normally you would just use the "patch" utility to apply the patch to your file.
 
Michael D. Black
Senior Scientist
Advanced Analytics Directorate
Northrop Grumman Information Systems
 

________________________________

From: sqlite-users-boun...@sqlite.org on behalf of 
jsarc...@nanotronicsimaging.com
Sent: Wed 11/3/2010 10:22 AM
To: sqlite-users@sqlite.org
Subject: EXTERNAL:Re: [sqlite] R*Tree module and double precision?



>From: "Black, Michael (IS)" <michael.bla...@ngc.com> I made a patch 
>which seems to do this for you...
>Use this switch to enable double precision on RTREE /DRTREE_DOUBLE

I am interested in this as well.  Will this patch be included in a future 
version of SQLite?  Or, if not, how best to make use of this patch if I 
normally use the amalgamation from C++.
Jeff Archer
Nanotronics Imaging
jsarc...@nanotronicsimaging.com
<330>819.4615
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