X-Git-Url: http://gitweb.michael.orlitzky.com/?p=sage.d.git;a=blobdiff_plain;f=mjo%2Feja%2Feja_utils.py;h=3942e70811c6d69e59c9581d23f17af05c261dfa;hp=0b2d2a315989949c2431641c8f82dea9b576f9b8;hb=cf5e64b70869df65c7bb38888de54b1083e60d45;hpb=5154ccb39a8fd2d69330ae440bd6d92a12f67e7c

diff --git a/mjo/eja/eja_utils.py b/mjo/eja/eja_utils.py
index 0b2d2a3..3942e70 100644
--- a/mjo/eja/eja_utils.py
+++ b/mjo/eja/eja_utils.py
@@ -2,6 +2,40 @@ from sage.functions.other import sqrt
 from sage.matrix.constructor import matrix
 from sage.modules.free_module_element import vector
 
+def _charpoly_sage_input(s):
+    r"""
+    Helper function that you can use on the string output from sage
+    to convert a charpoly coefficient into the corresponding input
+    to be cached.
+
+    SETUP::
+
+        sage: from mjo.eja.eja_utils import _charpoly_sage_input
+
+    EXAMPLES::
+
+        sage: J = JordanSpinEJA(4,QQ)
+        sage: J._charpoly_coefficients()[0]
+        X1^2 - X2^2 - X3^2 - X4^2
+        sage: _charpoly_sage_input("X1^2 - X2^2 - X3^2 - X4^2")
+        'X[0]**2 - X[1]**2 - X[2]**2 - X[3]**2'
+
+    """
+    import re
+
+    exponent_out = r"\^"
+    exponent_in = r"**"
+
+    digit_out = r"X([0-9]+)"
+
+    def replace_digit(m):
+        # m is a match object
+        return "X[" + str(int(m.group(1)) - 1) + "]"
+
+    s = re.sub(exponent_out, exponent_in, s)
+    return re.sub(digit_out, replace_digit, s)
+
+
 def _scale(x, alpha):
     r"""
     Scale the vector, matrix, or cartesian-product-of-those-things
@@ -54,7 +88,9 @@ def _all2list(x):
     SETUP::
 
         sage: from mjo.eja.eja_utils import _all2list
-        sage: from mjo.octonions import Octonions, OctonionMatrixAlgebra
+        sage: from mjo.hurwitz import (QuaternionMatrixAlgebra,
+        ....:                          Octonions,
+        ....:                          OctonionMatrixAlgebra)
 
     EXAMPLES::
 
@@ -86,6 +122,13 @@ def _all2list(x):
         sage: _all2list(OctonionMatrixAlgebra(1).one())
         [1, 0, 0, 0, 0, 0, 0, 0]
 
+    ::
+
+        sage: _all2list(QuaternionAlgebra(QQ, -1, -1).one())
+        [1, 0, 0, 0]
+        sage: _all2list(QuaternionMatrixAlgebra(1).one())
+        [1, 0, 0, 0]
+
     ::
 
         sage: V1 = VectorSpace(QQ,2)