def test_field_4():
f = Field(4)
assert [str(e) for e in f.elements] == ['0', '1', 'x', 'x + 1']
assert f.elements == [
RemainderPoly(coef_list=[IntMod(0)]),
RemainderPoly(coef_list=[IntMod(1)]),
RemainderPoly(coef_list=[IntMod(0), IntMod(1)]),
RemainderPoly(coef_list=[IntMod(1), IntMod(1)])
]
def test_plus_different_degrees():
IntMod.modulus = 2
rp1 = RemainderPoly(coef_list=[IntMod(0), IntMod(1)])
rp2 = RemainderPoly(coef_list=[IntMod(1), IntMod(1), IntMod(1)])
rp = rp1 + rp2
rp_expected = RemainderPoly(coef_list=[IntMod(1), IntMod(0), IntMod(1)])
assert rp == rp_expected
def test_plus_no_quotient():
IntMod.modulus = 2
rp1 = RemainderPoly(coef_list=[IntMod(0), IntMod(1)])
rp2 = RemainderPoly(coef_list=[IntMod(1), IntMod(1)])
rp = rp1 + rp2
rp_expected = RemainderPoly(coef_list=[IntMod(1)])
assert rp == rp_expected
def test_times_no_residue_needed():
IntMod.modulus = 3
qp = PolyMod([IntMod(1), IntMod(1), IntMod(1), IntMod(1)])
RemainderPoly.quotient = qp
rp1 = RemainderPoly(coef_list=[IntMod(1), IntMod(1)])
rp2 = RemainderPoly(coef_list=[IntMod(1), IntMod(1)])
rp = rp1 * rp2
rp_expected = RemainderPoly(coef_list=[IntMod(1), IntMod(2), IntMod(1)])
assert rp == rp_expected
def test_create_with_quotient():
IntMod.modulus = 7
qp = PolyMod([IntMod(1), IntMod(2), IntMod(1)])
RemainderPoly.quotient = qp
rp = RemainderPoly([IntMod(1), IntMod(4), IntMod(6), IntMod(4), IntMod(1)])
rp._residue() # pylint: disable=protected-access
x = str(rp)
assert x == '0'
def test_create_no_quotient():
IntMod.modulus = 0
rp = RemainderPoly(coef_list=[
IntMod(1), IntMod(4),
IntMod(6), IntMod(4),
IntMod(1)
])
x = str(rp)
assert x == 'x^4 + 4x^3 + 6x^2 + 4x + 1'