int main() {
array double complex v[4] = {complex(1,2),3,4,5}; /* (1+i2)x^3 + 3x^2 + 4x + 5 */
int n = 4;
array double complex a[n-1][n-1];
a = ccompanionmatrix(v);
printf("ccompanionmatrix(a) =\n%f\n", a);
}

ccompanionmatrix(a) =
complex(-0.600000,1.200000) complex(-0.800000,1.600000) complex(-1.000000,2.000000)
complex(1.000000,0.000000) complex(0.000000,0.000000) complex(0.000000,0.000000)
complex(0.000000,0.000000) complex(1.000000,0.000000) complex(0.000000,0.000000)