[Octave-bug-tracker] [bug #56170] [octave forge] (signal) results from fir1 differ from Matlab (inaccurate?)

[John W. Eaton]

URL:
  <https://savannah.gnu.org/bugs/?56170>

                 Summary: [octave forge] (signal) results from fir1 differ
from Matlab (inaccurate?)
                 Project: GNU Octave
            Submitted by: jwe
            Submitted on: Fri 19 Apr 2019 02:30:42 PM UTC
                Category: Octave Forge Package
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Inaccurate Result
                  Status: None
             Assigned to: None
         Originator Name: jwe
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: dev
        Operating System: Any

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Details:

I received a report about differences between the results produced by Matlab
and Octave's fir1 functions.  The example given was:


fir1 (2048, 100/(48000/2), 'low')


The result from Matlab is in column 1 of the attached file (fir1-example.dat)
and the results I see for Octave are in column 2.  I see a maximum difference
of almost 3%

In another case, the difference is larger.  I misinterpreted the original
example and asked for confirmation on the maintainers mailing list for the
following instead:


fir1 (2048, 100/48000/2, 'low')


The result from Matlab is in column 3 of the data file and the corresponding
result from Octave is in column 4.  Here the maximum difference is about 5%

I'm using the development version of Octave and the signal package.  Octave hg
id:  64461ccf3039  and signal package hg id:  2adde4d8b905.



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File Attachments:


-------------------------------------------------------
Date: Fri 19 Apr 2019 02:30:42 PM UTC  Name: fir1-example.dat  Size: 124KiB  
By: jwe

<http://savannah.gnu.org/bugs/download.php?file_id=46798>

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