# v_lpczz2ss

## PURPOSE

V_LPCZZ2SS Convert z-plane poles to s-plane poles SS=(ZZ)

## SYNOPSIS

function ss=v_lpczz2ss(zz)

## DESCRIPTION

    V_LPCZZ2SS Convert z-plane poles to s-plane poles SS=(ZZ)
    the s-plane is in units of Normalized Hz and so the imaginary part
     of each ss() value is in the range +-0.5

     If you multiply ss by the sample frequency, a formant with
     frequency f and bandwidth b will give an s-plane pole-pair
     of approximately -b/2 +-j*f

     The inverse function is zz=v_lpcss2zz(ss)

## CROSS-REFERENCE INFORMATION

This function calls:

This function is called by:

## SOURCE CODE

    0001 function ss=v_lpczz2ss(zz)
    0002 %V_LPCZZ2SS Convert z-plane poles to s-plane poles SS=(ZZ)
    0003 %the s-plane is in units of Normalized Hz and so the imaginary part
    0004 % of each ss() value is in the range +-0.5
    0005 %
    0006 % If you multiply ss by the sample frequency, a formant with
    0007 % frequency f and bandwidth b will give an s-plane pole-pair
    0008 % of approximately -b/2 +-j*f
    0009 %
    0010 % The inverse function is zz=v_lpcss2zz(ss)
    0011
    0012
    0013 %      Copyright (C) Mike Brookes 1997
    0014 %      Version: $Id: v_lpczz2ss.m 10865 2018-09-21 17:22:45Z dmb $
    0015 %
    0016 %   VOICEBOX is a MATLAB toolbox for speech processing.
    0017 %   Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html
    0018 %
    0019 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    0020 %   This program is free software; you can redistribute it and/or modify
    0021 %   it under the terms of the GNU Lesser General Public License as published by
    0022 %   the Free Software Foundation; either version 3 of the License, or
    0023 %   (at your option) any later version.
    0024 %
    0025 %   This program is distributed in the hope that it will be useful,
    0026 %   but WITHOUT ANY WARRANTY; without even the implied warranty of
    0027 %   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    0028 %   GNU Lesser General Public License for more details.
    0029 %
    0030 %   You can obtain a copy of the GNU Lesser General Public License from
    0031 %   https://www.gnu.org/licenses/ .
    0032 %
    0033 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    0034
    0035 ss=log(max(zz,1e-8))*0.5/pi;