phase and magnitude computation
[phi,db]=phasemag(z [,mod])
:z matrix or row vector of complex numbers. : :mod character string
- :mod=’c’ “continuous” representation between -infinity and +360
- degrees (default)
: :mod=’m’ representation between -360 and 0 degrees :
: :phi phases (in degree) of z. : :db magnitude (in Db) :
phasemag computes the phases and magnitudes of the entries of a complex matrix. For mod=’c’ phasemag computes phi(:,i+1) to minimize the distance with phi(:,i), i.e. it tries to obtain a “continuous representation” of the phase.
To obtain the phase between -%pi and %pi use phi=atan(imag(z),real(z))
s=`poly`_(0,'s');
h=`syslin`_('c',1/((s+5)*(s+10)*(100+6*s+s*s)*(s+.3)));
[frq,rf]=`repfreq`_(h,0.1,20,0.005);
`scf`_();
`plot2d`_(frq',phasemag(rf,'c')');
`scf`_();
`plot2d`_(frq',phasemag(rf,'m')');