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zp2sos error: cplxpair: could not pair all complex numbers

From: hale812
Subject: zp2sos error: cplxpair: could not pair all complex numbers
Date: Wed, 4 Jan 2017 21:30:14 -0800 (PST)

Again, the problem exactly as described 5 years ago. And nothing was fixed:

Trying to calculate 6th order Chebyshev filter, getting an error out of the

The code:
conf.stages=6; %Stages Chebyshev type2 filter
conf.reject=40; %-dB out-of-band rejection
conf.fsamp=1000; %1000Hz sampling frequency
fpL=0.52915085925565918945068233369966; %Hz singular rejection frequency
(pole) below the band
fpH=491.55617297547132693580351769924; %Hz singular rejection frequency
(pole) above the band
%[fpL.*2 ./conf.fsamp,fpH.*2 ./conf.fsamp]=[0.00107164775883543,  

[z,p,k]=cheby2(conf.stages,conf.reject,[fpL.*2 ./conf.fsamp,fpH.*2

error: cplxpair: could not pair all complex numbers
error: called from
    cplxpair at line 128 column 9
    cplxreal at line 52 column 9
    zp2sos at line 77 column 10

These (fpL, fpH) numbers look weird, but that is what fsolve has suggested,
when optimizing the filter. Technically, they are completely legit and
should not crash.

This is really an awful kind of problem. Octave is becoming popular among
engineers, but such fundamental problems, like failing signal toolbox, or
crashing when computing 32bit numbers in long loops, reduce it's reputation
to nothing. I just can not finish my work without rewriting everything in
Fortran or C.

5 years guys! The problem is there longer than 5 years and nobody done a
thing about it.

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