Create helper PolyDict.terms_of_degree(d)

1 files changed, 6 insertions, 0 deletions

diff --git a/polymatrix/polymatrix/index.py b/polymatrix/polymatrix/index.py
index ba9d508..bab991f 100644
--- a/polymatrix/polymatrix/index.py
+++ b/polymatrix/polymatrix/index.py
@@ -201,6 +201,12 @@ class PolyDict(UserDict[MonomialIndex, int | float]):
         # This is an alias for readability
         yield from self.items()
 
+    def terms_of_degree(self, d: int) -> Iterable[tuple[MonomialIndex, int | float]]:
+        """ Iterate over terms of degree `d` with a non-zero coefficient. """
+        yield from ((m, coeff)
+                    for m, coeff in self.terms()
+                        if m.degree == d)
+
     def monomials(self) -> Iterable[MonomialIndex]:
         """ Get monomials that compose the polynomial. """
         # This is an alias for readability