sage.combinat: More # optional

Author: Matthias Koeppe

src/sage/combinat/words/finite_word.py

@@ -5977,7 +5977,7 @@ def is_sturmian_factor(self):
 
             sage: words.LowerMechanicalWord(random(),alphabet='01')[:100].is_sturmian_factor()
             True
-            sage: words.CharacteristicSturmianWord(random())[:100].is_sturmian_factor()
+            sage: words.CharacteristicSturmianWord(random())[:100].is_sturmian_factor()     # optional - sage.rings.real_mpfr
             True
 
         ::

src/sage/combinat/words/morphic.py

@@ -32,7 +32,7 @@
 from sage.misc.lazy_import import lazy_import
 from sage.rings.infinity import Infinity
 
-lazy_import('sage.modules.free_module_element', 'import vector')
+lazy_import('sage.modules.free_module_element', 'vector')
 
 
 class WordDatatype_morphic(WordDatatype_callable):

src/sage/combinat/words/paths.py

@@ -188,7 +188,6 @@
 lazy_import("sage.plot.all", ["arrow", "line", "polygon", "point", "Graphics"])
 from sage.modules.free_module_element import vector
 from sage.rings.integer_ring import ZZ
-from sage.rings.number_field.number_field import QuadraticField
 from sage.rings.real_mpfr import RR
 from .word_datatypes import (WordDatatype_str,
                             WordDatatype_list,
@@ -202,6 +201,8 @@
                             WordDatatype_callable)
 from sage.matrix.constructor import vector_on_axis_rotation_matrix
 
+lazy_import('sage.rings.number_field.number_field', 'QuadraticField')
+
 
 #######################################################################
 #                                                                     #

src/sage/combinat/words/word_generators.py

@@ -778,9 +778,9 @@ def CharacteristicSturmianWord(self, slope, alphabet=(0, 1), bits=None):
 
             sage: words.CharacteristicSturmianWord(1/golden_ratio^2)                    # optional - sage.symbolic
             word: 0100101001001010010100100101001001010010...
-            sage: words.CharacteristicSturmianWord(4/5)
+            sage: words.CharacteristicSturmianWord(4/5)                                 # optional - sage.rings.real_mpfr
             word: 11110
-            sage: words.CharacteristicSturmianWord(5/14)
+            sage: words.CharacteristicSturmianWord(5/14)                                # optional - sage.rings.real_mpfr
             word: 01001001001001
             sage: words.CharacteristicSturmianWord(pi - 3)                              # optional - sage.symbolic
             word: 0000001000000100000010000001000000100000...