Example #1
0
def test_generate():
    from sympy.ntheory.generate import sieve
    sieve._reset()
    assert nextprime(-4) == 2
    assert nextprime(2) == 3
    assert nextprime(5) == 7
    assert nextprime(12) == 13
    assert prevprime(3) == 2
    assert prevprime(7) == 5
    assert prevprime(13) == 11
    assert prevprime(19) == 17
    assert prevprime(20) == 19

    sieve.extend_to_no(9)
    assert sieve._list[-1] == 23

    assert sieve._list[-1] < 31
    assert 31 in sieve

    assert nextprime(90) == 97
    assert nextprime(10**40) == (10**40 + 121)
    assert prevprime(97) == 89
    assert prevprime(10**40) == (10**40 - 17)

    assert list(sieve.primerange(10, 1)) == []
    assert list(sieve.primerange(5, 9)) == [5, 7]
    sieve._reset(prime=True)
    assert list(sieve.primerange(2, 12)) == [2, 3, 5, 7, 11]

    assert list(sieve.totientrange(5, 15)) == [4, 2, 6, 4, 6, 4, 10, 4, 12, 6]
    sieve._reset(totient=True)
    assert list(sieve.totientrange(3, 13)) == [2, 2, 4, 2, 6, 4, 6, 4, 10, 4]
    assert list(sieve.totientrange(900, 1000)) == [totient(x) for x in range(900, 1000)]
    assert list(sieve.totientrange(0, 1)) == []
    assert list(sieve.totientrange(1, 2)) == [1]

    assert list(sieve.mobiusrange(5, 15)) == [-1, 1, -1, 0, 0, 1, -1, 0, -1, 1]
    sieve._reset(mobius=True)
    assert list(sieve.mobiusrange(3, 13)) == [-1, 0, -1, 1, -1, 0, 0, 1, -1, 0]
    assert list(sieve.mobiusrange(1050, 1100)) == [mobius(x) for x in range(1050, 1100)]
    assert list(sieve.mobiusrange(0, 1)) == []
    assert list(sieve.mobiusrange(1, 2)) == [1]

    assert list(primerange(10, 1)) == []
    assert list(primerange(2, 7)) == [2, 3, 5]
    assert list(primerange(2, 10)) == [2, 3, 5, 7]
    assert list(primerange(1050, 1100)) == [1051, 1061,
        1063, 1069, 1087, 1091, 1093, 1097]
    s = Sieve()
    for i in range(30, 2350, 376):
        for j in range(2, 5096, 1139):
            A = list(s.primerange(i, i + j))
            B = list(primerange(i, i + j))
            assert A == B
    s = Sieve()
    assert s[10] == 29

    assert nextprime(2, 2) == 5

    raises(ValueError, lambda: totient(0))

    raises(ValueError, lambda: reduced_totient(0))

    raises(ValueError, lambda: primorial(0))

    assert mr(1, [2]) is False

    func = lambda i: (i**2 + 1) % 51
    assert next(cycle_length(func, 4)) == (6, 2)
    assert list(cycle_length(func, 4, values=True)) == \
        [17, 35, 2, 5, 26, 14, 44, 50, 2, 5, 26, 14]
    assert next(cycle_length(func, 4, nmax=5)) == (5, None)
    assert list(cycle_length(func, 4, nmax=5, values=True)) == \
        [17, 35, 2, 5, 26]
    sieve.extend(3000)
    assert nextprime(2968) == 2969
    assert prevprime(2930) == 2927
    raises(ValueError, lambda: prevprime(1))
def test_generate():
    from sympy.ntheory.generate import sieve
    sieve._reset()
    assert nextprime(-4) == 2
    assert nextprime(2) == 3
    assert nextprime(5) == 7
    assert nextprime(12) == 13
    assert prevprime(3) == 2
    assert prevprime(7) == 5
    assert prevprime(13) == 11
    assert prevprime(19) == 17
    assert prevprime(20) == 19

    sieve.extend_to_no(9)
    assert sieve._list[-1] == 23

    assert sieve._list[-1] < 31
    assert 31 in sieve

    assert nextprime(90) == 97
    assert nextprime(10**40) == (10**40 + 121)
    assert prevprime(97) == 89
    assert prevprime(10**40) == (10**40 - 17)

    assert list(sieve.primerange(10, 1)) == []
    assert list(sieve.primerange(5, 9)) == [5, 7]
    sieve._reset(prime=True)
    assert list(sieve.primerange(2, 12)) == [2, 3, 5, 7, 11]

    assert list(sieve.totientrange(5, 15)) == [4, 2, 6, 4, 6, 4, 10, 4, 12, 6]
    sieve._reset(totient=True)
    assert list(sieve.totientrange(3, 13)) == [2, 2, 4, 2, 6, 4, 6, 4, 10, 4]
    assert list(sieve.totientrange(
        900, 1000)) == [totient(x) for x in range(900, 1000)]
    assert list(sieve.totientrange(0, 1)) == []
    assert list(sieve.totientrange(1, 2)) == [1]

    assert list(sieve.mobiusrange(5, 15)) == [-1, 1, -1, 0, 0, 1, -1, 0, -1, 1]
    sieve._reset(mobius=True)
    assert list(sieve.mobiusrange(3, 13)) == [-1, 0, -1, 1, -1, 0, 0, 1, -1, 0]
    assert list(sieve.mobiusrange(
        1050, 1100)) == [mobius(x) for x in range(1050, 1100)]
    assert list(sieve.mobiusrange(0, 1)) == []
    assert list(sieve.mobiusrange(1, 2)) == [1]

    assert list(primerange(10, 1)) == []
    assert list(primerange(2, 7)) == [2, 3, 5]
    assert list(primerange(2, 10)) == [2, 3, 5, 7]
    assert list(primerange(
        1050, 1100)) == [1051, 1061, 1063, 1069, 1087, 1091, 1093, 1097]
    s = Sieve()
    for i in range(30, 2350, 376):
        for j in range(2, 5096, 1139):
            A = list(s.primerange(i, i + j))
            B = list(primerange(i, i + j))
            assert A == B
    s = Sieve()
    assert s[10] == 29

    assert nextprime(2, 2) == 5

    raises(ValueError, lambda: totient(0))

    raises(ValueError, lambda: reduced_totient(0))

    raises(ValueError, lambda: primorial(0))

    assert mr(1, [2]) is False

    func = lambda i: (i**2 + 1) % 51
    assert next(cycle_length(func, 4)) == (6, 2)
    assert list(cycle_length(func, 4, values=True)) == \
        [17, 35, 2, 5, 26, 14, 44, 50, 2, 5, 26, 14]
    assert next(cycle_length(func, 4, nmax=5)) == (5, None)
    assert list(cycle_length(func, 4, nmax=5, values=True)) == \
        [17, 35, 2, 5, 26]
    sieve.extend(3000)
    assert nextprime(2968) == 2969
    assert prevprime(2930) == 2927
    raises(ValueError, lambda: prevprime(1))
Example #3
0
from sympy import generate

sieve._reset(
)  # An infinite list of prime numbers, implemented as a dynamically growing sieve of Eratosthenes.#When a lookup is
# requested involving an odd number that has not been sieved,the sieve is automatically extended up to that number.

print(13 in sieve)  # prints 'True' if the input is prime,

sieve.extend(40)  #for input n grows the sieve to contain all primes <= n

print(sieve[10])  # returns n th prime

sieve.extend_to_no(15)  # extends upto n th prime

# mobiusrange(a,b) genarates Mobius numbers for the range [a,b), means output will be a list.
Mob_func = sieve.mobiusrange(7, 12)
print('\n Mobius function outputs in the given range:', [i for i in Mob_func])

# primerange(a,b) generates all prime numbers in the range [a,b)
Prime_list = sieve.primerange(1, 5)
print('\n Primes in the given range are :', [i for i in Prime_list])

#search(n) return the indices i, j of the primes that bound n. If n is prime then i == j. Although n can be an expression,
# if ceiling cannot convert it to an integer then an error will be raised.
x, y = sieve.search(25)
print('\n The given input is in between ', '(', x, ',', y, ')', 'th Primes \n')

#totientrange(a, b) generates all totient numbers for the range [a, b). Simply it is a list of outputs
Totient_range = sieve.totientrange(1, 10)
print(' Values of Totient(n):', [i for i in Totient_range])