hand

2026-05-06 19:47:31 +07:00
parent 94d8682530
commit 12dbb7731b
9963 changed files with 2747894 additions and 0 deletions
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+# Impl routines common for all backends
+from itertools import combinations_with_replacement
+from math import comb
+
+def _monomial_powers_impl(ndim, degree):
+    """Return the powers for each monomial in a polynomial.
+
+    Parameters
+    ----------
+    ndim : int
+        Number of variables in the polynomial.
+    degree : int
+        Degree of the polynomial.
+
+    Returns
+    -------
+    (nmonos, ndim) int ndarray
+        Array where each row contains the powers for each variable in a
+        monomial.
+
+    """
+    nmonos = comb(degree + ndim, ndim)
+    out = [[0]*ndim for _ in range(nmonos)]
+    count = 0
+    for deg in range(degree + 1):
+        for mono in combinations_with_replacement(range(ndim), deg):
+            # `mono` is a tuple of variables in the current monomial with
+            # multiplicity indicating power (e.g., (0, 1, 1) represents x*y**2)
+            for var in mono:
+                out[count][var] += 1
+            count += 1
+    return out