Update docs

da/kzg_rs/rs.py

@@ -10,6 +10,16 @@ ExtendedData = Sequence[BLSFieldElement]
 
 
 def encode(polynomial: Polynomial, factor: int, roots_of_unity: Sequence[BLSFieldElement]) -> ExtendedData:
+    """
+    Encode a polynomial extending to the given factor
+    Parameters:
+        polynomial: Polynomial to be encoded
+        factor: Encoding factor
+        roots_of_unity: Powers of 2 sequence
+
+    Returns:
+        list: Extended data set
+    """
     assert factor >= 2
     assert len(polynomial)*factor <= len(roots_of_unity)
     return [polynomial.eval(e) for e in roots_of_unity[:len(polynomial)*factor]]
@@ -18,10 +28,28 @@ def encode(polynomial: Polynomial, factor: int, roots_of_unity: Sequence[BLSFiel
 def __interpolate(evaluations: List[int], roots_of_unity: List[int]) -> List[int]:
     """
     Lagrange interpolation
+
+    Parameters:
+        evaluations: List of evaluations
+        roots_of_unity: Powers of 2 sequence
+
+    Returns:
+        list: Coefficients of the interpolated polynomial
     """
     return list(map(int, interpolate_polynomialcoeff(roots_of_unity[:len(evaluations)], evaluations)))
 
 
 def decode(encoded: ExtendedData, roots_of_unity: Sequence[BLSFieldElement], original_len: int) -> Polynomial:
+    """
+    Decode a polynomial from an extended data-set and the roots of unity, cap to original length
+
+    Parameters:
+        encoded: Extended data set
+        roots_of_unity: Powers of 2 sequence
+        original_len: Original length of the encoded polynomial
+
+    Returns:
+        Polynomial: original polynomial
+    """
     coefs = __interpolate(list(map(int, encoded)), list(map(int, roots_of_unity)))[:original_len]
     return Polynomial([int(c) for c in coefs], BLS_MODULUS)