eja: optionally pass matrix space into FDEJA instead of guessing it.

[sage.d.git] / mjo / eja / eja_subalgebra.py

diff --git a/mjo/eja/eja_subalgebra.py b/mjo/eja/eja_subalgebra.py
index 024903c256f5af81e9567b77f29b92a4537f88f8..4458a7e06d9d905ab276665a210eb7dc8275320b 100644 (file)
--- a/mjo/eja/eja_subalgebra.py
+++ b/mjo/eja/eja_subalgebra.py
@@ -51,35 +51,35 @@ class FiniteDimensionalEJASubalgebraElement(FiniteDimensionalEJAElement):
             sage: J = RealSymmetricEJA(3)
             sage: x = sum(J.gens())
             sage: x
-            e0 + e1 + e2 + e3 + e4 + e5
+            b0 + b1 + b2 + b3 + b4 + b5
             sage: A = x.subalgebra_generated_by(orthonormalize=False)
             sage: A(x)
-            f1
+            c1
             sage: A(x).superalgebra_element()
-            e0 + e1 + e2 + e3 + e4 + e5
+            b0 + b1 + b2 + b3 + b4 + b5
             sage: y = sum(A.gens())
             sage: y
-            f0 + f1
+            c0 + c1
             sage: B = y.subalgebra_generated_by(orthonormalize=False)
             sage: B(y)
-            g1
+            d1
             sage: B(y).superalgebra_element()
-            f0 + f1
+            c0 + c1
 
         TESTS:
 
         We can convert back and forth faithfully::
 
             sage: set_random_seed()
-            sage: J = random_eja()
+            sage: J = random_eja(field=QQ, orthonormalize=False)
             sage: x = J.random_element()
-            sage: A = x.subalgebra_generated_by()
+            sage: A = x.subalgebra_generated_by(orthonormalize=False)
             sage: A(x).superalgebra_element() == x
             True
             sage: y = A.random_element()
             sage: A(y.superalgebra_element()) == y
             True
-            sage: B = y.subalgebra_generated_by()
+            sage: B = y.subalgebra_generated_by(orthonormalize=False)
             sage: B(y).superalgebra_element() == y
             True
 
@@ -110,28 +110,29 @@ class FiniteDimensionalEJASubalgebra(FiniteDimensionalEJA):
         ....:                    [0,0] ])
         sage: E22 = matrix(AA, [ [0,0],
         ....:                    [0,1] ])
-        sage: K1 = FiniteDimensionalEJASubalgebra(J, (J(E11),))
+        sage: K1 = FiniteDimensionalEJASubalgebra(J, (J(E11),), associative=True)
         sage: K1.one().to_matrix()
         [1 0]
         [0 0]
-        sage: K2 = FiniteDimensionalEJASubalgebra(J, (J(E22),))
+        sage: K2 = FiniteDimensionalEJASubalgebra(J, (J(E22),), associative=True)
         sage: K2.one().to_matrix()
         [0 0]
         [0 1]
 
     TESTS:
 
-    Ensure that our generator names don't conflict with the superalgebra::
+    Ensure that our generator names don't conflict with the
+    superalgebra::
 
         sage: J = JordanSpinEJA(3)
         sage: J.one().subalgebra_generated_by().gens()
-        (f0,)
+        (c0,)
         sage: J = JordanSpinEJA(3, prefix='f')
         sage: J.one().subalgebra_generated_by().gens()
         (g0,)
-        sage: J = JordanSpinEJA(3, prefix='b')
+        sage: J = JordanSpinEJA(3, prefix='a')
         sage: J.one().subalgebra_generated_by().gens()
-        (c0,)
+        (b0,)
 
     Ensure that we can find subalgebras of subalgebras::
 
@@ -139,7 +140,6 @@ class FiniteDimensionalEJASubalgebra(FiniteDimensionalEJA):
         sage: B = A.one().subalgebra_generated_by()
         sage: B.dimension()
         1
-
     """
     def __init__(self, superalgebra, basis, **kwargs):
         self._superalgebra = superalgebra
@@ -152,7 +152,7 @@ class FiniteDimensionalEJASubalgebra(FiniteDimensionalEJA):
         # try to "increment" the parent algebra's prefix, although
         # this idea goes out the window fast because some prefixen
         # are off-limits.
-        prefixen = [ 'f', 'g', 'h', 'a', 'b', 'c', 'd' ]
+        prefixen = ["b","c","d","e","f","g","h","l","m"]
         try:
             prefix = prefixen[prefixen.index(self._superalgebra.prefix()) + 1]
         except ValueError:
@@ -171,6 +171,7 @@ class FiniteDimensionalEJASubalgebra(FiniteDimensionalEJA):
                          jordan_product,
                          inner_product,
                          field=field,
+                         matrix_space=superalgebra.matrix_space(),
                          prefix=prefix,
                          **kwargs)
 
@@ -195,11 +196,14 @@ class FiniteDimensionalEJASubalgebra(FiniteDimensionalEJA):
             ....:                  [1,0,0] ])
             sage: x = J(X)
             sage: basis = ( x, x^2 ) # x^2 is the identity matrix
-            sage: K = FiniteDimensionalEJASubalgebra(J, basis, orthonormalize=False)
+            sage: K = FiniteDimensionalEJASubalgebra(J,
+            ....:                                    basis,
+            ....:                                    associative=True,
+            ....:                                    orthonormalize=False)
             sage: K(J.one())
-            f1
+            c1
             sage: K(J.one() + x)
-            f0 + f1
+            c0 + c1
 
         ::
 
@@ -210,19 +214,6 @@ class FiniteDimensionalEJASubalgebra(FiniteDimensionalEJA):
             return super()._element_constructor_(elt)
 
 
-
-    def matrix_space(self):
-        """
-        Return the matrix space of this algebra, which is identical to
-        that of its superalgebra.
-
-        This is correct "by definition," and avoids a mismatch when
-        the subalgebra is trivial (with no matrix basis elements to
-        infer anything from) and the parent is not.
-        """
-        return self.superalgebra().matrix_space()
-
-
     def superalgebra(self):
         """
         Return the superalgebra that this algebra was generated from.