property galois.FLFSR.feedback_poly : Poly

The feedback polynomial f(x)=−c0xn−c1xn−1−⋯−cn−2x2−cn−1x+1 that defines the feedback arithmetic. The feedback polynomial is the reciprocal of the characteristic polynomial f(x)=xnc(x−1).

Examples

In [1]: c = galois.primitive_poly(7, 4); c
Out[1]: Poly(x^4 + x^2 + 3x + 5, GF(7))

In [2]: lfsr = galois.FLFSR(c.reverse()); lfsr
Out[2]: <Fibonacci LFSR: f(x) = 5x^4 + 3x^3 + x^2 + 1 over GF(7)>

In [3]: lfsr.feedback_poly
Out[3]: Poly(5x^4 + 3x^3 + x^2 + 1, GF(7))

In [4]: lfsr.feedback_poly == lfsr.characteristic_poly.reverse()
Out[4]: True