phasemag phase and magnitude computation

## Syntax

                [phi, db] = phasemag(z)
                [phi, db] = phasemag(z, mod)

## 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')');

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); plot2d(frq',phasemag(rf,'c')'); 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); plot2d(frq',phasemag(rf,'m')');

## See also

- repfreq
- gainplot
- atan
- bode