switching to high quality piper tts and added label translations

venv_piper/lib/python3.12/site-packages/sympy/ntheory/multinomial.py

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+from sympy.utilities.misc import as_int
+
+
+def binomial_coefficients(n):
+    """Return a dictionary containing pairs :math:`{(k1,k2) : C_kn}` where
+    :math:`C_kn` are binomial coefficients and :math:`n=k1+k2`.
+
+    Examples
+    ========
+
+    >>> from sympy.ntheory import binomial_coefficients
+    >>> binomial_coefficients(9)
+    {(0, 9): 1, (1, 8): 9, (2, 7): 36, (3, 6): 84,
+     (4, 5): 126, (5, 4): 126, (6, 3): 84, (7, 2): 36, (8, 1): 9, (9, 0): 1}
+
+    See Also
+    ========
+
+    binomial_coefficients_list, multinomial_coefficients
+    """
+    n = as_int(n)
+    d = {(0, n): 1, (n, 0): 1}
+    a = 1
+    for k in range(1, n//2 + 1):
+        a = (a * (n - k + 1))//k
+        d[k, n - k] = d[n - k, k] = a
+    return d
+
+
+def binomial_coefficients_list(n):
+    """ Return a list of binomial coefficients as rows of the Pascal's
+    triangle.
+
+    Examples
+    ========
+
+    >>> from sympy.ntheory import binomial_coefficients_list
+    >>> binomial_coefficients_list(9)
+    [1, 9, 36, 84, 126, 126, 84, 36, 9, 1]
+
+    See Also
+    ========
+
+    binomial_coefficients, multinomial_coefficients
+    """
+    n = as_int(n)
+    d = [1] * (n + 1)
+    a = 1
+    for k in range(1, n//2 + 1):
+        a = (a * (n - k + 1))//k
+        d[k] = d[n - k] = a
+    return d
+
+
+def multinomial_coefficients(m, n):
+    r"""Return a dictionary containing pairs ``{(k1,k2,..,km) : C_kn}``
+    where ``C_kn`` are multinomial coefficients such that
+    ``n=k1+k2+..+km``.
+
+    Examples
+    ========
+
+    >>> from sympy.ntheory import multinomial_coefficients
+    >>> multinomial_coefficients(2, 5) # indirect doctest
+    {(0, 5): 1, (1, 4): 5, (2, 3): 10, (3, 2): 10, (4, 1): 5, (5, 0): 1}
+
+    Notes
+    =====
+
+    The algorithm is based on the following result:
+
+    .. math::
+        \binom{n}{k_1, \ldots, k_m} =
+        \frac{k_1 + 1}{n - k_1} \sum_{i=2}^m \binom{n}{k_1 + 1, \ldots, k_i - 1, \ldots}
+
+    Code contributed to Sage by Yann Laigle-Chapuy, copied with permission
+    of the author.
+
+    See Also
+    ========
+
+    binomial_coefficients_list, binomial_coefficients
+    """
+    m = as_int(m)
+    n = as_int(n)
+    if not m:
+        if n:
+            return {}
+        return {(): 1}
+    if m == 2:
+        return binomial_coefficients(n)
+    if m >= 2*n and n > 1:
+        return dict(multinomial_coefficients_iterator(m, n))
+    t = [n] + [0] * (m - 1)
+    r = {tuple(t): 1}
+    if n:
+        j = 0  # j will be the leftmost nonzero position
+    else:
+        j = m
+    # enumerate tuples in co-lex order
+    while j < m - 1:
+        # compute next tuple
+        tj = t[j]
+        if j:
+            t[j] = 0
+            t[0] = tj
+        if tj > 1:
+            t[j + 1] += 1
+            j = 0
+            start = 1
+            v = 0
+        else:
+            j += 1
+            start = j + 1
+            v = r[tuple(t)]
+            t[j] += 1
+        # compute the value
+        # NB: the initialization of v was done above
+        for k in range(start, m):
+            if t[k]:
+                t[k] -= 1
+                v += r[tuple(t)]
+                t[k] += 1
+        t[0] -= 1
+        r[tuple(t)] = (v * tj) // (n - t[0])
+    return r
+
+
+def multinomial_coefficients_iterator(m, n, _tuple=tuple):
+    """multinomial coefficient iterator
+
+    This routine has been optimized for `m` large with respect to `n` by taking
+    advantage of the fact that when the monomial tuples `t` are stripped of
+    zeros, their coefficient is the same as that of the monomial tuples from
+    ``multinomial_coefficients(n, n)``. Therefore, the latter coefficients are
+    precomputed to save memory and time.
+
+    >>> from sympy.ntheory.multinomial import multinomial_coefficients
+    >>> m53, m33 = multinomial_coefficients(5,3), multinomial_coefficients(3,3)
+    >>> m53[(0,0,0,1,2)] == m53[(0,0,1,0,2)] == m53[(1,0,2,0,0)] == m33[(0,1,2)]
+    True
+
+    Examples
+    ========
+
+    >>> from sympy.ntheory.multinomial import multinomial_coefficients_iterator
+    >>> it = multinomial_coefficients_iterator(20,3)
+    >>> next(it)
+    ((3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0), 1)
+    """
+    m = as_int(m)
+    n = as_int(n)
+    if m < 2*n or n == 1:
+        mc = multinomial_coefficients(m, n)
+        yield from mc.items()
+    else:
+        mc = multinomial_coefficients(n, n)
+        mc1 = {}
+        for k, v in mc.items():
+            mc1[_tuple(filter(None, k))] = v
+        mc = mc1
+
+        t = [n] + [0] * (m - 1)
+        t1 = _tuple(t)
+        b = _tuple(filter(None, t1))
+        yield (t1, mc[b])
+        if n:
+            j = 0  # j will be the leftmost nonzero position
+        else:
+            j = m
+        # enumerate tuples in co-lex order
+        while j < m - 1:
+            # compute next tuple
+            tj = t[j]
+            if j:
+                t[j] = 0
+                t[0] = tj
+            if tj > 1:
+                t[j + 1] += 1
+                j = 0
+            else:
+                j += 1
+                t[j] += 1
+
+            t[0] -= 1
+            t1 = _tuple(t)
+            b = _tuple(filter(None, t1))
+            yield (t1, mc[b])