[Octave-bug-tracker] [bug #30787] Table lookup performance is really slow

[anonymous]

URL:
  <http://savannah.gnu.org/bugs/?30787>

                 Summary: Table lookup performance is really slow
                 Project: GNU Octave
            Submitted by: None
            Submitted on: Mon 16 Aug 2010 11:01:26 AM UTC
                Category: None
                Severity: 3 - Normal
              Item Group: None
                  Status: None
             Assigned to: None
         Originator Name: Ondrej Such
        Originator Email: address@hidden
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 3.2.2
        Operating System: Microsoft Windows

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Details:

Try out commands

problem1 = readmps("afiro.mps");
problem2 = readmps("80bau3b.mps");

The former one is very slow, and the latter does not even complete in any
reasonable amount of time.

The MPS files are standard ones from a NETLIB collection, and the author of
readmps says his code runs fine in Matlab (code downloaded from
http://infohost.nmt.edu/~borchers/readmps.html). 

The slowness of the code appears to be caused by linear time lookups in
coltable created by calling newtable() Octave built-in function.



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File Attachments:


-------------------------------------------------------
Date: Mon 16 Aug 2010 11:01:27 AM UTC  Name: readmps.zip  Size: 8kB   By:
None

<http://savannah.gnu.org/bugs/download.php?file_id=21234>
-------------------------------------------------------
Date: Mon 16 Aug 2010 11:01:27 AM UTC  Name: afiro.mps  Size: 3kB   By: None

<http://savannah.gnu.org/bugs/download.php?file_id=21235>

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