bugGNU Octave - Bugs: bug #53979, convhull(pts) and convhull(X,Y,Z)...


bug #53979: convhull(pts) and convhull(X,Y,Z) should work for Matlab compatibility

Submitted by:  None
Submitted on:  Fri 25 May 2018 05:32:46 AM UTC  
Category:  Octave Function Severity:  3 - Normal
Priority:  5 - Normal Item Group:  Matlab Compatibility
Status:  Fixed Assigned to:  None
Originator Name:  b9 Originator Email:  -email is unavailable-
Open/Closed:  Closed Release:  dev
Operating System:  Any

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Mon 19 Nov 2018 01:20:51 AM UTC, comment #2:

I modified convhull.m to add support for 1- and 3-input calling styles. See changeset https://hg.savannah.gnu.org/hgweb/octave/rev/e97a0d4ed5d0. This will be a part of Octave 5.0 scheduled for release at the end of the year.

Marking as fixed and closing report.

Rik <rik5>
Project Administrator
Tue 12 Jun 2018 06:47:26 PM UTC, comment #1:

Matlab regularly changes the syntax of their functions slightly. Marking bug as confirmed. This is a easy fix for anyone who wants to try their hand at coding an m-file.

The function to change is scripts/geometry/convhull.m and there is already a template in scripts/geometry/delaunay.m where 1, 2, or 3 arguments can be passed.

Rik <rik5>
Project Administrator
Fri 25 May 2018 05:32:46 AM UTC, original submission:

It appears that matlab's convhull() now accepts a single matrix:

matlab> convhull(pts)

while Octave still requires separate X and Y arrays:

octave> convhull(pts(:,1), pts(:,2))

In addition, matlab's convhull accepts three arrays as representing 3-D space:

matlab> convhull(X, Y, Z)

Octave's convhull is limited to 2-D.

Please compare:


I think these two problems should be simple to fix as convenience wrappers to convhulln.

One slight trickiness might be that the single matrix can be any number of dimensions, not just 2-D. It is likely that straight mapping to convhulln, which already handles that, will work, but I am not sure of the details.



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    Follow 6 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2018-11-19 rik5 StatusConfirmed => Fixed
        Open/ClosedOpen => Closed
    2018-06-12 rik5 StatusNone => Confirmed
        Releaseother => dev
        Operating SystemGNU/Linux => Any
        Summaryconvhull(pts) and convhull(X,Y,Z) should work => convhull(pts) and convhull(X,Y,Z) should work for Matlab compatibility

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