phasemag

Arguments

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)

Description

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))

Examples

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')');

See also

• repfreq — frequency response
• gainplot — magnitude plot
• atan — 2-quadrant and 4-quadrant inverse tangent
• bode — Bode plot