DOC: Update symbol wording and add to docstrings.

numpy · Sep 22, 2020 · 5b028aa · 5b028aa
1 parent 0ae8891
commit 5b028aa
Showing 1 changed file with 10 additions and 2 deletions.
diff --git a/numpy/polynomial/_polybase.py b/numpy/polynomial/_polybase.py
@@ -40,8 +40,8 @@ class ABCPolyBase(abc.ABC):
     symbol : str, optional
         Symbol used to represent the independent variable in string 
         representations of the polynomial expression, e.g. for printing.
-        The symbol must be a non-empty string, the first character of which
-        is an alphabetical character. Default value is 'x'.
+        The symbol must be a non-empty string where the first character is
+        non-numeric. Default value is 'x'.
 
     Attributes
     ----------
@@ -983,6 +983,8 @@ class domain in NumPy 1.4 and ``None`` in later versions.
             value is the default class domain
 
             .. versionadded:: 1.6.0
+        symbol : str, optional
+            Symbol representing the independent variable. Default is 'x'.
 
         Returns
         -------
@@ -1039,6 +1041,8 @@ def fromroots(cls, roots, domain=[], window=None, symbol='x'):
         window : {None, array_like}, optional
             Window for the returned series. If None the class window is
             used. The default is None.
+        symbol : str, optional
+            Symbol representing the independent variable. Default is 'x'.
 
         Returns
         -------
@@ -1079,6 +1083,8 @@ def identity(cls, domain=None, window=None, symbol='x'):
             ``[beg, end]``, where ``beg`` and ``end`` are the endpoints of
             the window. If None is given then the class window is used. The
             default is None.
+        symbol : str, optional
+            Symbol representing the independent variable. Default is 'x'.
 
         Returns
         -------
@@ -1115,6 +1121,8 @@ def basis(cls, deg, domain=None, window=None, symbol='x'):
             ``[beg, end]``, where ``beg`` and ``end`` are the endpoints of
             the window. If None is given then the class window is used. The
             default is None.
+        symbol : str, optional
+            Symbol representing the independent variable. Default is 'x'.
 
         Returns
         -------