Scilab Function

kpure - continuous SISO system limit feedback gain

### Sequence d'appel

  `g=kpure(sys)`

### Parametres

- `sys` : SISO linear system (syslin)
- `g` : constant

### Description

`kpure(sys)` computes the gains `g` such that the system `sys` feedback by g (`sys/.g`) has poles on imaginary axis.

### Exemples

    s=poly(0,'s');
    h=syslin('c',(s-1)/(1+5*s+s^2+s^3))
    xbasc();evans(h)
    g=kpure(h)
    hf=h/.g(1)
    roots(denom(hf))

### Voir aussi

`evans` `krac2`