]> gitweb.michael.orlitzky.com - sage.d.git/blobdiff - mjo/hurwitz.py
eja: refactor all matrix classes upwards (note: everything broken).
[sage.d.git] / mjo / hurwitz.py
index 75e856862f735251775506d237aa8b3e1b726a67..1f7c9dc3781a844d6d77a1e63168c52340bf6770 100644 (file)
@@ -306,6 +306,31 @@ class Octonions(CombinatorialFreeModule):
 
 
 class HurwitzMatrixAlgebraElement(MatrixAlgebraElement):
+    def conjugate_transpose(self):
+        r"""
+        Return the conjugate-transpose of this matrix.
+
+        SETUP::
+
+            sage: from mjo.hurwitz import HurwitzMatrixAlgebra
+
+        EXAMPLES::
+
+            sage: A = HurwitzMatrixAlgebra(2, QQbar, ZZ)
+            sage: M = A([ [ I,   2*I],
+            ....:         [ 3*I, 4*I] ])
+            +------+------+
+            | -1*I | -3*I |
+            +------+------+
+            | -2*I | -4*I |
+            +------+------+
+
+        """
+        entries = [ [ self[j,i].conjugate()
+                      for j in range(self.ncols())]
+                    for i in range(self.nrows()) ]
+        return self.parent()._element_constructor_(entries)
+
     def is_hermitian(self):
         r"""
 
@@ -315,13 +340,15 @@ class HurwitzMatrixAlgebraElement(MatrixAlgebraElement):
 
         EXAMPLES::
 
-            sage: A = HurwitzMatrixAlgebra(QQbar, ZZ, 2)
+            sage: A = HurwitzMatrixAlgebra(2, QQbar, ZZ)
             sage: M = A([ [ 0,I],
             ....:         [-I,0] ])
             sage: M.is_hermitian()
             True
 
         """
+        # A tiny bit faster than checking equality with the conjugate
+        # transpose.
         return all( self[i,j] == self[j,i].conjugate()
                     for i in range(self.nrows())
                     for j in range(self.ncols()) )
@@ -344,13 +371,13 @@ class HurwitzMatrixAlgebra(MatrixAlgebra):
     """
     Element = HurwitzMatrixAlgebraElement
 
-    def __init__(self, entry_algebra, scalars, n, **kwargs):
+    def __init__(self, n, entry_algebra, scalars, **kwargs):
         from sage.rings.all import RR
         if not scalars.is_subring(RR):
             # Not perfect, but it's what we're using.
             raise ValueError("scalar field is not real")
 
-        super().__init__(entry_algebra, scalars, n, **kwargs)
+        super().__init__(n, entry_algebra, scalars, **kwargs)
 
     def entry_algebra_gens(self):
         r"""
@@ -382,15 +409,15 @@ class HurwitzMatrixAlgebra(MatrixAlgebra):
         sets of generators have cartinality 1,2,4, and 8 as you'd
         expect::
 
-            sage: HurwitzMatrixAlgebra(AA, AA, 2).entry_algebra_gens()
+            sage: HurwitzMatrixAlgebra(2, AA, AA).entry_algebra_gens()
             (1,)
-            sage: HurwitzMatrixAlgebra(QQbar, AA, 2).entry_algebra_gens()
+            sage: HurwitzMatrixAlgebra(2, QQbar, AA).entry_algebra_gens()
             (1, I)
             sage: Q = QuaternionAlgebra(AA,-1,-1)
-            sage: HurwitzMatrixAlgebra(Q, AA, 2).entry_algebra_gens()
+            sage: HurwitzMatrixAlgebra(2, Q, AA).entry_algebra_gens()
             (1, i, j, k)
             sage: O = Octonions()
-            sage: HurwitzMatrixAlgebra(O, AA, 2).entry_algebra_gens()
+            sage: HurwitzMatrixAlgebra(2, O, AA).entry_algebra_gens()
             (e0, e1, e2, e3, e4, e5, e6, e7)
 
         """
@@ -414,16 +441,57 @@ class OctonionMatrixAlgebra(HurwitzMatrixAlgebra):
 
     SETUP::
 
-        sage: from mjo.hurwitz import OctonionMatrixAlgebra
+        sage: from mjo.hurwitz import Octonions, OctonionMatrixAlgebra
 
     EXAMPLES::
 
         sage: OctonionMatrixAlgebra(3)
         Module of 3 by 3 matrices with entries in Octonion algebra with base
         ring Algebraic Real Field over the scalar ring Algebraic Real Field
-        sage: OctonionMatrixAlgebra(3,QQ)
-        Module of 3 by 3 matrices with entries in Octonion algebra with base
-        ring Rational Field over the scalar ring Rational Field
+
+    ::
+
+        sage: OctonionMatrixAlgebra(3,scalars=QQ)
+        Module of 3 by 3 matrices with entries in Octonion algebra with
+        base ring Rational Field over the scalar ring Rational Field
+
+    ::
+
+        sage: O = Octonions(RR)
+        sage: A = OctonionMatrixAlgebra(1,O)
+        sage: A
+        Module of 1 by 1 matrices with entries in Octonion algebra with
+        base ring Real Field with 53 bits of precision over the scalar
+        ring Algebraic Real Field
+        sage: A.one()
+        +---------------------+
+        | 1.00000000000000*e0 |
+        +---------------------+
+        sage: A.gens()
+        (+---------------------+
+        | 1.00000000000000*e0 |
+        +---------------------+,
+        +---------------------+
+        | 1.00000000000000*e1 |
+        +---------------------+,
+        +---------------------+
+        | 1.00000000000000*e2 |
+        +---------------------+,
+        +---------------------+
+        | 1.00000000000000*e3 |
+        +---------------------+,
+        +---------------------+
+        | 1.00000000000000*e4 |
+        +---------------------+,
+        +---------------------+
+        | 1.00000000000000*e5 |
+        +---------------------+,
+        +---------------------+
+        | 1.00000000000000*e6 |
+        +---------------------+,
+        +---------------------+
+        | 1.00000000000000*e7 |
+        +---------------------+)
 
     ::
 
@@ -439,8 +507,8 @@ class OctonionMatrixAlgebra(HurwitzMatrixAlgebra):
 
     ::
 
-        sage: A1 = OctonionMatrixAlgebra(1,QQ)
-        sage: A2 = OctonionMatrixAlgebra(1,QQ)
+        sage: A1 = OctonionMatrixAlgebra(1,scalars=QQ)
+        sage: A2 = OctonionMatrixAlgebra(1,scalars=QQ)
         sage: cartesian_product([A1,A2])
         Module of 1 by 1 matrices with entries in Octonion algebra with
         base ring Rational Field over the scalar ring Rational Field (+)
@@ -456,11 +524,12 @@ class OctonionMatrixAlgebra(HurwitzMatrixAlgebra):
         True
 
     """
-    def __init__(self, n, scalars=AA, prefix="E", **kwargs):
-        super().__init__(Octonions(field=scalars),
+    def __init__(self, n, entry_algebra=None, scalars=AA, **kwargs):
+        if entry_algebra is None:
+            entry_algebra = Octonions(field=scalars)
+        super().__init__(n,
+                         entry_algebra,
                          scalars,
-                         n,
-                         prefix=prefix,
                          **kwargs)
 
 class QuaternionMatrixAlgebra(HurwitzMatrixAlgebra):
@@ -482,11 +551,40 @@ class QuaternionMatrixAlgebra(HurwitzMatrixAlgebra):
         Module of 3 by 3 matrices with entries in Quaternion
         Algebra (-1, -1) with base ring Algebraic Real Field
         over the scalar ring Algebraic Real Field
-        sage: QuaternionMatrixAlgebra(3,QQ)
+
+    ::
+
+        sage: QuaternionMatrixAlgebra(3,scalars=QQ)
         Module of 3 by 3 matrices with entries in Quaternion
         Algebra (-1, -1) with base ring Rational Field over
         the scalar ring Rational Field
 
+    ::
+
+        sage: Q = QuaternionAlgebra(RDF, -1, -1)
+        sage: A = QuaternionMatrixAlgebra(1,Q)
+        sage: A
+        Module of 1 by 1 matrices with entries in Quaternion Algebra
+        (-1.0, -1.0) with base ring Real Double Field over the scalar
+        ring Algebraic Real Field
+        sage: A.one()
+        +-----+
+        | 1.0 |
+        +-----+
+        sage: A.gens()
+        (+-----+
+        | 1.0 |
+        +-----+,
+        +---+
+        | i |
+        +---+,
+        +---+
+        | j |
+        +---+,
+        +---+
+        | k |
+        +---+)
+
     ::
 
         sage: A = QuaternionMatrixAlgebra(2)
@@ -501,8 +599,8 @@ class QuaternionMatrixAlgebra(HurwitzMatrixAlgebra):
 
     ::
 
-        sage: A1 = QuaternionMatrixAlgebra(1,QQ)
-        sage: A2 = QuaternionMatrixAlgebra(2,QQ)
+        sage: A1 = QuaternionMatrixAlgebra(1,scalars=QQ)
+        sage: A2 = QuaternionMatrixAlgebra(2,scalars=QQ)
         sage: cartesian_product([A1,A2])
         Module of 1 by 1 matrices with entries in Quaternion Algebra
         (-1, -1) with base ring Rational Field over the scalar ring
@@ -519,11 +617,14 @@ class QuaternionMatrixAlgebra(HurwitzMatrixAlgebra):
         True
 
     """
-    def __init__(self, n, scalars=AA, **kwargs):
-        # The -1,-1 gives us the "usual" definition of quaternion
-        from sage.algebras.quatalg.quaternion_algebra import QuaternionAlgebra
-        Q = QuaternionAlgebra(scalars,-1,-1)
-        super().__init__(Q, scalars, n, **kwargs)
+    def __init__(self, n, entry_algebra=None, scalars=AA, **kwargs):
+        if entry_algebra is None:
+            # The -1,-1 gives us the "usual" definition of quaternion
+            from sage.algebras.quatalg.quaternion_algebra import (
+                QuaternionAlgebra
+            )
+            entry_algebra = QuaternionAlgebra(scalars,-1,-1)
+        super().__init__(n, entry_algebra, scalars, **kwargs)
 
 
 class ComplexMatrixAlgebra(HurwitzMatrixAlgebra):
@@ -545,10 +646,31 @@ class ComplexMatrixAlgebra(HurwitzMatrixAlgebra):
         sage: ComplexMatrixAlgebra(3)
         Module of 3 by 3 matrices with entries in Algebraic Field
         over the scalar ring Algebraic Real Field
-        sage: ComplexMatrixAlgebra(3,QQ)
+
+    ::
+
+        sage: ComplexMatrixAlgebra(3,scalars=QQ)
         Module of 3 by 3 matrices with entries in Algebraic Field
         over the scalar ring Rational Field
 
+    ::
+
+        sage: A = ComplexMatrixAlgebra(1,CC)
+        sage: A
+        Module of 1 by 1 matrices with entries in Complex Field with
+        53 bits of precision over the scalar ring Algebraic Real Field
+        sage: A.one()
+        +------------------+
+        | 1.00000000000000 |
+        +------------------+
+        sage: A.gens()
+        (+------------------+
+        | 1.00000000000000 |
+        +------------------+,
+        +--------------------+
+        | 1.00000000000000*I |
+        +--------------------+)
+
     ::
 
         sage: A = ComplexMatrixAlgebra(2)
@@ -563,8 +685,8 @@ class ComplexMatrixAlgebra(HurwitzMatrixAlgebra):
 
     ::
 
-        sage: A1 = ComplexMatrixAlgebra(1,QQ)
-        sage: A2 = ComplexMatrixAlgebra(2,QQ)
+        sage: A1 = ComplexMatrixAlgebra(1,scalars=QQ)
+        sage: A2 = ComplexMatrixAlgebra(2,scalars=QQ)
         sage: cartesian_product([A1,A2])
         Module of 1 by 1 matrices with entries in Algebraic Field over
         the scalar ring Rational Field (+) Module of 2 by 2 matrices with
@@ -579,6 +701,8 @@ class ComplexMatrixAlgebra(HurwitzMatrixAlgebra):
         True
 
     """
-    def __init__(self, n, scalars=AA, **kwargs):
-        from sage.rings.all import QQbar
-        super().__init__(QQbar, scalars, n, **kwargs)
+    def __init__(self, n, entry_algebra=None, scalars=AA, **kwargs):
+        if entry_algebra is None:
+            from sage.rings.all import QQbar
+            entry_algebra = QQbar
+        super().__init__(n, entry_algebra, scalars, **kwargs)