bugGNU Octave - Bugs: bug #45542, griddatan unable to perform...

 
 

bug #45542: griddatan unable to perform 4-dimensional interpolation.

Submitted by:  None
Submitted on:  Mon 13 Jul 2015 02:25:03 PM UTC  
 
Category: Octave FunctionSeverity: 3 - Normal
Priority: 5 - NormalItem Group: Incorrect Result
Status: In ProgressAssigned to: None
Originator Name: Juho IipponenOriginator Email: -unavailable-
Open/Closed: OpenRelease: 4.0.0
Operating System: GNU/Linux

Add a New Comment(Rich Markup)
   

You are not logged in

Please log in, so followups can be emailed to you.

 

Sat 02 Jul 2016 02:08:24 AM UTC, comment #2:

Thanks for the patch, Juho.

Could you please prepare a diff of the file from the original, rather than providing a complete new file? That makes it easier to apply to the current codebase.

Lachlan Andrew <lachlan>
Project Member
Mon 20 Jul 2015 01:11:15 PM UTC, comment #1:

Taking the transpose of "y(tri(tri_list,:))" before multiplication (see original submission) seems to be the correct course of action. However, it only works if a point lies within the convex hull, when both vectors to be multiplied are non-empty. Therefore, I have added a guard before that line:

I have attached the fixed griddatan.m function, but I would want someone more knowledgeable to have a look at it.

(file #34467)

Juho Iipponen <juppiega>
Mon 13 Jul 2015 02:25:03 PM UTC, original submission:

The griddatan function seems to be unable to perform 4-dimensional interpolation (in e.g. (x, y, z, time)-coordinates). While running the attached script "test_griddatan.m" with test input data "test_griddatan.mat", the function fails while attempting to fill in the interpolated values for output (last line of griddatan.m to be executed for linear interpolation). The error message is:

To me, this seems to be caused by different shape of vectors "y(tri(tri_list,:))" and "bary_list", which are multiplied element-wise. In this example, the former is of size 5x1, while the latter is of size 1x5. If I transpose "y(tri(tri_list,:))" before multiplication, the last line yields a result of 3.1866e-14, which is very close to the one given by Matlab (3.1858e-14). However, I have no experience with multidimensional geometry, so I'm not sure if taking the transpose is the correct solution.

Anonymous

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach File(s):
   
   
Comment:
   

Attached Files
file #34467:  griddatan.m added by juppiega (4KiB - text/x-objcsrc)
file #34436:  test_griddatan.m added by None (106B - text/x-objcsrc)
file #34437:  test_griddatan.mat added by None (1KiB - application/octet-stream)

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -unavailable- added by lachlan (Posted a comment)
  • -unavailable- added by rik5 (Updated the item)
  • -unavailable- added by juppiega (Updated the item)
  • -unavailable- added by None (Submitted the item)
  •  

    Do you think this task is very important?
    If so, you can click here to add your encouragement to it.
    This task has 0 encouragements so far.

    Only project members can vote.

     

    Please enter the title of George Orwell's famous dystopian book (it's a date):

     

     

    Follow 6 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Sat 02 Jul 2016 02:08:24 AM UTClachlanStatusPatch Submitted=>In Progress
    Tue 01 Dec 2015 05:47:57 PM UTCrik5Item GroupSegfault, Bus Error, etc.=>Incorrect Result
      StatusNone=>Patch Submitted
    Mon 20 Jul 2015 01:11:15 PM UTCjuppiegaAttached File-=>Added griddatan.m, #34467
    Mon 13 Jul 2015 02:25:03 PM UTCNoneAttached File-=>Added test_griddatan.m, #34436
      Attached File-=>Added test_griddatan.mat, #34437

    Back to the top


    Powered by Savane 3.1-cleanup1