[Octave-bug-tracker] [bug #51145] conv2 and filter2: incompatible results on empty inputs

[Hartmut]

URL:
  <http://savannah.gnu.org/bugs/?51145>

                 Summary: conv2 and filter2: incompatible results on empty
inputs
                 Project: GNU Octave
            Submitted by: hardy
            Submitted on: Tue 30 May 2017 06:12:29 PM UTC
                Category: Octave Function
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Matlab Compatibility
                  Status: None
             Assigned to: None
         Originator Name: 
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 4.2.1
        Operating System: Any

    _______________________________________________________

Details:

This happens in Octave 4.2.1:

>> conv2([], ones(5))
ans = [](0x0)

>> conv2(ones(5),[])
ans = [](0x0)

>> filter2([], ones(5))
ans = [](0x0)

>> filter2(ones(5),[])
ans = [](0x0)


This is the corresponding Matlab (R2014b) output:

>> conv2([], ones(5))
ans =
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0

>> conv2(ones(5),[])
ans =

     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0

>> filter2([], ones(5))
ans =
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0
     0     0     0     0     0

>> filter2(ones(5),[])
ans =
     []


So the Octave version of the functions conv2 and filter2 always return an
empty matrix if any input value is an empty matrix. But the Matlab version
returns mostly (except for one of four cases, funny) a full zero matrix in
this case.





    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?51145>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.gnu.org/