bugGNU Octave - Bugs: bug #38948, interp1 output has wrong order...


bug #38948: interp1 output has wrong order with 'nearest'

Submitted by:  None
Submitted on:  Thu 09 May 2013 10:44:10 AM UTC  
Category:  Octave Function Severity:  3 - Normal
Priority:  5 - Normal Item Group:  Incorrect Result
Status:  Fixed Assigned to:  None
Originator Name:  Michiel Originator Email:  -email is unavailable-
Open/Closed:  Closed Release:  3.6.2
Operating System:  Microsoft Windows

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Tue 22 Oct 2013 04:06:13 PM UTC, comment #3:

I applied the interp patch since Olaf inspected it and Mike agrees that it fixes the current problem without introducing new 'make check' errors. Closing report.

Rik <rik5>
Project Administrator
Sat 27 Jul 2013 09:40:49 PM UTC, comment #2:

The attached patch does fix the given problem and all tests for interp1 and ppval still pass. I'm also not pretending to understand ppval, so I can't comment any further.

Mike Miller <mtmiller>
Project Administrator
Fri 10 May 2013 11:42:00 AM UTC, comment #1:

Attached is a patch that fixes this issue. It should be noted that I did not try to understand the code in ppval (sorcerer's apprentice method). I just ensured that the shape of intermediate matrix (before final reshaping) was consistent between "nearest" and higher order methods.

(file #28060)

Pantxo Diribarne <pantxo>
Project Member
Thu 09 May 2013 10:44:10 AM UTC, original submission:


I noticed strange behavior with interp1 in combination with 'nearest'.

interp1(x,y, x(2:end-1)+[0.5 -0.5], 'nearest')
ans =

3 7
2 6
4 8
3 7
5 9
4 8
6 10
5 9
Notice that the output is given in the first column instead of per row
I would expect:
ans =

3 2
4 3
5 4
6 5
7 6
8 7
9 8
10 9
my current workaround is:
interp1(x,y, x(2:end-1)+[0.5 -0.5], 'nearest')(:), 2,8)'





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Attach Files:

Attached Files
file #28060:  ppval_nearest_shape.patch added by pantxo (979B - text/x-patch)


Depends on the following items: None found

Items that depend on this one: None found


Carbon-Copy List
  • -email is unavailable- added by rik5 (Posted a comment)
  • -email is unavailable- added by mtmiller (Posted a comment)
  • -email is unavailable- added by pantxo (Updated the item)
  • -email is unavailable- added by None (Submitted the item)

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    Follow 6 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2013-10-22 rik5 StatusPatch Submitted => Fixed
        Open/ClosedOpen => Closed
    2013-07-27 mtmiller CategoryNone => Octave Function
        Item GroupNone => Incorrect Result
        StatusNone => Patch Submitted
    2013-05-10 pantxo Attached File- => Added ppval_nearest_shape.patch, #28060

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