fix imports in doctests, and add a tutorial on lazy import into globa…

…l namespace
sagemath · Nov 6, 2014 · b68e76b · b68e76b
1 parent 2bc92ad
commit b68e76b
Show file tree

Hide file tree

Showing 2 changed files with 55 additions and 15 deletions.
diff --git a/src/sage/algebras/divided_power_algebra.py b/src/sage/algebras/divided_power_algebra.py
@@ -67,6 +67,26 @@ class UnivariateDividedPowerAlgebra(CombinatorialFreeModule):
     map :meth:`from_shuffle_algebra`) sends `t_i` to the word
     `x x \cdots x` (with `i` factors `x`).
 
+    .. NOTE::
+
+        Due to this being a toy implementation (and essentially a
+        particular case of the shuffle algebra), the univariate
+        divided power algebra is not available in the global
+        namespace for immediate interactive use. Instead, it
+        needs to be explicitly imported before using::
+
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
+            sage: A = UnivariateDividedPowerAlgebra(Zmod(9)); A
+            The divided power algebra over Ring of integers modulo 9
+
+        If you want to implement an algebra which needs not be
+        imported in order to be called, you need to add a
+        ``lazy_import`` statement to ``src/sage/algebras/all.py``.
+        In the case of the univariate divided power algebra, it
+        would look as follows::
+
+            lazy_import('sage.algebras.divided_power_algebra', 'UnivariateDividedPowerAlgebra')
+
     INPUT:
 
     - ``R``: base ring (a commutative ring).
@@ -78,7 +98,7 @@ class UnivariateDividedPowerAlgebra(CombinatorialFreeModule):
 
     EXAMPLES::
 
-        sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+        sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
         sage: A = UnivariateDividedPowerAlgebra(ZZ); A
         The divided power algebra over Integer Ring
         sage: TestSuite(A).run()
@@ -117,7 +137,7 @@ def one(self):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(ZZ)
             sage: A.one()
             B[0]
@@ -144,7 +164,7 @@ def product_on_basis(self, left, right):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: B = UnivariateDividedPowerAlgebra(ZZ).basis()
             sage: B[3]*B[4]
             35*B[7]
@@ -161,7 +181,7 @@ def coproduct_on_basis(self, t):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(ZZ)
             sage: B = A.basis()
             sage: A.coproduct(B[4])
@@ -180,7 +200,7 @@ def counit_on_basis(self, t):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(ZZ)
             sage: B = A.basis()
             sage: A.counit(B[3])
@@ -200,7 +220,7 @@ def antipode_on_basis(self, t):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(ZZ)
             sage: B = A.basis()
             sage: A.antipode(B[4]+B[5])
@@ -229,7 +249,7 @@ def degree_on_basis(self, t):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(ZZ)
             sage: A.degree_on_basis(3)
             3
@@ -249,7 +269,7 @@ def algebra_generators(self):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(ZZ)
             sage: A.algebra_generators()
             Family (Non negative integers)
@@ -268,7 +288,7 @@ def to_shuffle_algebra(self, letter="x"):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(QQ)
             sage: A_bas = A.basis()
             sage: tosh_x = A.to_shuffle_algebra()
@@ -298,7 +318,7 @@ def from_shuffle_algebra(self, letter="x"):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateDividedPowerAlgebra
+            sage: from sage.algebras.divided_power_algebra import UnivariateDividedPowerAlgebra
             sage: A = UnivariateDividedPowerAlgebra(QQ)
             sage: frosh_x = A.from_shuffle_algebra()
             sage: ShA_x = ShuffleAlgebra(QQ, 'x')

diff --git a/src/sage/algebras/quantum_divided_power_algebra.py b/src/sage/algebras/quantum_divided_power_algebra.py
@@ -53,6 +53,26 @@ class UnivariateQuantumDividedPowerAlgebra(CombinatorialFreeModule):
     isomorphic to the polynomial ring `R[t]` by the algebra
     isomorphism which sends every `t_i` to `t^i / i!_q`.
 
+    .. NOTE::
+
+        Due to this being a toy implementation, the univariate
+        quantum divided power algebra is not available in the
+        global namespace for immediate interactive use. Instead,
+        it needs to be explicitly imported before using::
+
+            sage: from sage.algebras.quantum_divided_power_algebra import UnivariateQuantumDividedPowerAlgebra
+            sage: A = UnivariateQuantumDividedPowerAlgebra(Zmod(9), Zmod(9)(2)); A
+            The quantum divided power algebra over Ring of integers modulo 9
+             with quantum parameter 1
+
+        If you want to implement an algebra which needs not be
+        imported in order to be called, you need to add a
+        ``lazy_import`` statement to ``src/sage/algebras/all.py``.
+        In the case of the univariate quantum divided power
+        algebra, it would look as follows::
+
+            lazy_import('sage.algebras.quantum_divided_power_algebra', 'UnivariateQuantumDividedPowerAlgebra')
+
     INPUT:
 
     - ``R`` (default: `\ZZ`): base ring (a commutative ring).
@@ -67,7 +87,7 @@ class UnivariateQuantumDividedPowerAlgebra(CombinatorialFreeModule):
 
     EXAMPLES::
 
-        sage: from sage.algebras.all import UnivariateQuantumDividedPowerAlgebra
+        sage: from sage.algebras.quantum_divided_power_algebra import UnivariateQuantumDividedPowerAlgebra
         sage: A = UnivariateQuantumDividedPowerAlgebra(ZZ, 1); A
         The quantum divided power algebra over Integer Ring
          with quantum parameter 1
@@ -163,7 +183,7 @@ def one(self):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateQuantumDividedPowerAlgebra
+            sage: from sage.algebras.quantum_divided_power_algebra import UnivariateQuantumDividedPowerAlgebra
             sage: A = UnivariateQuantumDividedPowerAlgebra(ZZ)
             sage: A.one()
             B[0]
@@ -190,7 +210,7 @@ def product_on_basis(self, left, right):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateQuantumDividedPowerAlgebra
+            sage: from sage.algebras.quantum_divided_power_algebra import UnivariateQuantumDividedPowerAlgebra
             sage: A = UnivariateQuantumDividedPowerAlgebra(ZZ)
             sage: B = A.basis()
             sage: B[2]*B[3]
@@ -214,7 +234,7 @@ def degree_on_basis(self, t):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateQuantumDividedPowerAlgebra
+            sage: from sage.algebras.quantum_divided_power_algebra import UnivariateQuantumDividedPowerAlgebra
             sage: A = UnivariateQuantumDividedPowerAlgebra(ZZ)
             sage: A.degree_on_basis(3)
             3
@@ -234,7 +254,7 @@ def algebra_generators(self):
 
         EXAMPLES::
 
-            sage: from sage.algebras.all import UnivariateQuantumDividedPowerAlgebra
+            sage: from sage.algebras.quantum_divided_power_algebra import UnivariateQuantumDividedPowerAlgebra
             sage: A = UnivariateQuantumDividedPowerAlgebra(ZZ)
             sage: A.algebra_generators()
             Family (Non negative integers)