[Octave-bug-tracker] [bug #63440] [octave forge] (signal) sosfilt - NaN

[Charles Praplan]

Follow-up Comment #3, bug #63440 (project octave):

After some further testing, I propose following solution for the function

zp2sos:

  Problem:
  With current implementation of zp2sos, sos(i, 4) may be zero and this is
  unfortunately not supported by the fuction sosfilt.

  Solution:
   - The real poles and zeros must be combined (as the complex conjugates
ones)
   - Leading zeros present in numerator and denominator are removed
     [0, 1, 1, 0, 1, 2] -> [1, 1, 0, 1, 2, 0]


Additionally, a bug has been found in

sos2tf: 

  Problem:
  If several trailing zeros were present in numerator and denominator, only
one
  of them were removed in numerator (index for A was not incremented)

  Correction:
  - same index for A as for B (line 87) because index for A was not
incremented


Updated functions and corresponding diff files are appended!




(file #54164, file #54165, file #54166, file #54167)

    _______________________________________________________

Additional Item Attachment:

File name: zp2sos.m                       Size:6 KB
    <https://file.savannah.gnu.org/file/zp2sos.m?file_id=54164>

File name: sos2tf.m                       Size:5 KB
    <https://file.savannah.gnu.org/file/sos2tf.m?file_id=54165>

File name: zp2sos.diff                    Size:1 KB
    <https://file.savannah.gnu.org/file/zp2sos.diff?file_id=54166>

File name: sos2tf.diff                    Size:0 KB
    <https://file.savannah.gnu.org/file/sos2tf.diff?file_id=54167>



    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/bugs/?63440>

_______________________________________________
Message sent via Savannah
https://savannah.gnu.org/