use tensor letter for unicode of tensor symbol

Author: fchapoton

src/sage/categories/signed_tensor.py

@@ -5,15 +5,16 @@
 
 - Travis Scrimshaw (2019-07): initial version
 """
-#*****************************************************************************
+# ****************************************************************************
 #  Copyright (C) 2019 Travis Scrimshaw <tcscrims at gamil.com>
 #
 #  Distributed under the terms of the GNU General Public License (GPL)
 #                  http://www.gnu.org/licenses/
-#*****************************************************************************
+# ****************************************************************************
 
 from sage.categories.covariant_functorial_construction import CovariantFunctorialConstruction, CovariantConstructionCategory
 
+
 class SignedTensorProductFunctor(CovariantFunctorialConstruction):
     """
     A singleton class for the signed tensor functor.
@@ -51,6 +52,7 @@ class SignedTensorProductFunctor(CovariantFunctorialConstruction):
     _functor_name = "tensor"
     _functor_category = "SignedTensorProducts"
     symbol = " # "
+    unicode_symbol = " ⨂ "
 
     def _repr_(self):
         """
@@ -64,8 +66,10 @@ def _repr_(self):
         #   default _repr_
         return "The signed tensor functorial construction"
 
+
 tensor_signed = SignedTensorProductFunctor()
 
+
 class SignedTensorProductsCategory(CovariantConstructionCategory):
     r"""
     An abstract base class for all SignedTensorProducts's categories.
@@ -110,4 +114,3 @@ def base(self):
             Integer Ring
         """
         return self.base_category().base()
-

src/sage/categories/tensor.py

@@ -5,15 +5,16 @@
 
  - Nicolas M. Thiery (2008-2010): initial revision and refactorization
 """
-#*****************************************************************************
+# ****************************************************************************
 #  Copyright (C) 2008-2010 Nicolas M. Thiery <nthiery at users.sf.net>
 #
 #  Distributed under the terms of the GNU General Public License (GPL)
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
 from sage.categories.covariant_functorial_construction import CovariantFunctorialConstruction, CovariantConstructionCategory
 
+
 class TensorProductFunctor(CovariantFunctorialConstruction):
     """
     A singleton class for the tensor functor.
@@ -46,8 +47,12 @@ class TensorProductFunctor(CovariantFunctorialConstruction):
     _functor_name = "tensor"
     _functor_category = "TensorProducts"
     symbol = " # "
+    unicode_symbol = " ⨂ "
+
 
 tensor = TensorProductFunctor()
+
+
 """
 The tensor product functorial construction
 
@@ -59,6 +64,7 @@ class TensorProductFunctor(CovariantFunctorialConstruction):
     The tensor functorial construction
 """
 
+
 class TensorProductsCategory(CovariantConstructionCategory):
     r"""
     An abstract base class for all TensorProducts's categories
@@ -100,4 +106,3 @@ def base(self):
             Integer Ring
         """
         return self.base_category().base()
-

src/sage/combinat/free_module.py

@@ -1311,7 +1311,8 @@ def __init__(self, modules, **options):
                                                for module in modules]).map(tuple)
             CombinatorialFreeModule.__init__(self, modules[0].base_ring(), indices, **options)
             # the following is not the best option, but it's better than nothing.
-            self._print_options['tensor_symbol'] = options.get('tensor_symbol', tensor.symbol)
+            if 'tensor_symbol' in options:
+                self._print_options['tensor_symbol'] = options['tensor_symbol']
 
         def _repr_(self):
             r"""
@@ -1381,7 +1382,7 @@ def _unicode_art_(self, term):
                 sage: R = NonCommutativeSymmetricFunctions(QQ).R()
                 sage: Partitions.options(diagram_str="#", convention="french")
                 sage: s = unicode_art(tensor((R[1,2], R[3,1,2]))); s
-                R    # R
+                R    ⨂ R
                  ┌┐     ┌┬┬┐
                  ├┼┐    └┴┼┤
                  └┴┘      ├┼┐
@@ -1395,9 +1396,9 @@ def _unicode_art_(self, term):
             if hasattr(self, "_print_options"):
                 symb = self._print_options['tensor_symbol']
                 if symb is None:
-                    symb = tensor.symbol
+                    symb = tensor.unicode_symbol
             else:
-                symb = tensor.symbol
+                symb = tensor.unicode_symbol
             return unicode_art(*(module._unicode_art_term(t)
                                  for module, t in zip(self._sets, term)),
                                sep=UnicodeArt([symb], breakpoints=[len(symb)]))

src/sage/structure/indexed_generators.py

@@ -73,12 +73,13 @@ class IndexedGenerators(object):
 
     - ``tensor_symbol`` -- string or ``None`` (default: ``None``),
       string to use for tensor product in the print representation. If
-      ``None``, use  ``sage.categories.tensor.symbol``.
+      ``None``, use  ``sage.categories.tensor.symbol`` and
+      ``sage.categories.tensor.unicode_symbol``.
 
     - ``sorting_key`` -- a key function (default: ``lambda x: x``),
       to use for sorting elements in the output of elements
 
-    - ``sorting_reverse`` -- bool (default: ``False``), if ``True`` 
+    - ``sorting_reverse`` -- bool (default: ``False``), if ``True``
       sort elements in reverse order in the output of elements
 
     - ``string_quotes`` -- bool (default: ``True``), if ``True`` then