[DP_OUT, STABLE, NZ, IWARN, INFO] = slicot_mc01td(DICO, DP_IN, P)
| Parameter | Description |
|---|---|
| DICO | Indicates whether the stability test to be applied to P(x) is in the continuous-time or discrete-time case as follows: = 'C': Continuous-time case; = 'D': Discrete-time case. |
| DP_IN | The degree of the polynomial P(x). |
| P | This array must contain the coefficients of P(x) in increasing powers of x. |
| Parameter | Description |
|---|---|
| DP_OUT | if P(DP+1) = 0.0 on entry, then DP contains the index of the highest power of x for which P(DP+1) != 0.0. |
| STABLE | Contains the value int32(1) if P(x) is stable and the value int32(0) otherwise. |
| NZ | If INFO = 0, contains the number of unstable zeros - that is, the number of zeros of P(x) in the right half-plane if DICO = 'C' or the number of zeros of P(x) outside the unit circle if DICO = 'D'. |
| IWARN | = 0: no warning; |
| INFO | = 0: successful exit; = 1: if on entry, P(x) is the zero polynomial;= 2: if the polynomial P(x) is most probably unstable. |
To determine whether or not a given polynomial P(x) with real coefficients is stable, either in the continuous-time or discrete-time case.
A polynomial is said to be stable in the continuous-time case if all its zeros lie in the left half-plane, and stable in the discrete-time case if all its zeros lie inside the unit circle.
DICO = 'C';
DP_IN = 4;
P = [2.0 0.0 1.0 -1.0 1.0];
[DP, STABLE, NZ, IWARN, INFO] = slicot_mc01td(DICO, DP_IN, P)| Version | Description |
|---|---|
| 1.0.0 | initial version |