[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

PSPP-BUG: [bug #37999] RANK assert-fails with TEMPORARY

From: John Darrington
Subject: PSPP-BUG: [bug #37999] RANK assert-fails with TEMPORARY
Date: Tue, 08 Jan 2013 09:47:50 +0000
User-agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20100101 Firefox/17.0

Follow-up Comment #3, bug #37999 (project pspp):

There are several problems, which I think need to be dealt with separately
(but perhaps concurrently).

1. TEMPORARY needs to create an internal variable, which records
   the original positions of the cases.

2. RANK currently is implemented in a rather funny way with regard
   to splits.  It performs its initial sort before considering
   splits.  This was done as an optimisation effort - if the split
   variable and the rank variable happen to be the same, then only
   one sort is required.   However this way of doing things makes
   the procedure hard to maintain.  I think we should remove this
   optimisation and tidy up a bit before trying to fix the problem.
   After the problem is fixed, we can consider optimisation.

3. RANK currently creates an "internal" variable (called
   $ORDER).   This   will no longer be required in the case of
   TEMPORARY, because it will have been done by [1].  But if
   there is no TEMPORARY in effect, we will still have to do it 
   in RANK itself.  We need to make sure that in both cases, it
   is done consistently (ideally using the same code).


Reply to this item at:


  Message sent via/by Savannah

reply via email to

[Prev in Thread] Current Thread [Next in Thread]