Initialisation du repository de Beta

venv/lib/python3.12/site-packages/sympy/holonomic/tests/test_recurrence.py

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+from sympy.holonomic.recurrence import RecurrenceOperators, RecurrenceOperator
+from sympy.core.symbol import symbols
+from sympy.polys.domains.rationalfield import QQ
+
+
+def test_RecurrenceOperator():
+    n = symbols('n', integer=True)
+    R, Sn = RecurrenceOperators(QQ.old_poly_ring(n), 'Sn')
+    assert Sn*n == (n + 1)*Sn
+    assert Sn*n**2 == (n**2+1+2*n)*Sn
+    assert Sn**2*n**2 == (n**2 + 4*n + 4)*Sn**2
+    p = (Sn**3*n**2 + Sn*n)**2
+    q = (n**2 + 3*n + 2)*Sn**2 + (2*n**3 + 19*n**2 + 57*n + 52)*Sn**4 + (n**4 + 18*n**3 + \
+        117*n**2 + 324*n + 324)*Sn**6
+    assert p == q
+
+
+def test_RecurrenceOperatorEqPoly():
+    n = symbols('n', integer=True)
+    R, Sn = RecurrenceOperators(QQ.old_poly_ring(n), 'Sn')
+    rr = RecurrenceOperator([n**2, 0, 0], R)
+    rr2 = RecurrenceOperator([n**2, 1, n], R)
+    assert not rr == rr2
+
+    # polynomial comparison issue, see https://github.com/sympy/sympy/pull/15799
+    # should work once that is solved
+    # d = rr.listofpoly[0]
+    # assert rr == d
+
+    d2 = rr2.listofpoly[0]
+    assert not rr2 == d2
+
+
+def test_RecurrenceOperatorPow():
+    n = symbols('n', integer=True)
+    R, _ = RecurrenceOperators(QQ.old_poly_ring(n), 'Sn')
+    rr = RecurrenceOperator([n**2, 0, 0], R)
+    a = RecurrenceOperator([R.base.one], R)
+    for m in range(10):
+        assert a == rr**m
+        a *= rr