X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=mjo%2Fcone%2Fsymmetric_psd.py;h=ef5d477ce67aa4f40a3466c48904888ddfaa840b;hb=bcdc6431e034e6f7a9d6ddcb3282cecadfab597b;hp=514d0392c1fbe4fbae72057a87fd5524744c0668;hpb=a4f22c00f915d4c20f5105039d647540c18b3d83;p=sage.d.git

diff --git a/mjo/cone/symmetric_psd.py b/mjo/cone/symmetric_psd.py
index 514d039..ef5d477 100644
--- a/mjo/cone/symmetric_psd.py
+++ b/mjo/cone/symmetric_psd.py
@@ -6,14 +6,6 @@ all symmetric positive-semidefinite matrices (as a subset of
 
 from sage.all import *
 
-# Sage doesn't load ~/.sage/init.sage during testing (sage -t), so we
-# have to explicitly mangle our sitedir here so that "mjo.symbolic"
-# resolves.
-from os.path import abspath
-from site import addsitedir
-addsitedir(abspath('../../'))
-
-
 def is_symmetric_psd(A):
     """
     Determine whether or not the matrix ``A`` is symmetric
@@ -28,6 +20,10 @@ def is_symmetric_psd(A):
     Either ``True`` if ``A`` is symmetric positive-semidefinite, or
     ``False`` otherwise.
 
+    SETUP::
+
+        sage: from mjo.cone.symmetric_psd import is_symmetric_psd
+
     EXAMPLES:
 
     Every completely positive matrix is symmetric
@@ -80,6 +76,10 @@ def unit_eigenvectors(A):
     A list of (eigenvalue, eigenvector) pairs where each eigenvector is
     associated with its paired eigenvalue of ``A`` and has norm `1`.
 
+    SETUP::
+
+        sage: from mjo.cone.symmetric_psd import unit_eigenvectors
+
     EXAMPLES::
 
         sage: A = matrix(QQ, [[0, 2, 3], [2, 0, 0], [3, 0, 0]])
@@ -145,6 +145,10 @@ def factor_psd(A):
     `$D$` will have dimension `$k \times k$`. In the end everything
     works out the same.
 
+    SETUP::
+
+        sage: from mjo.cone.symmetric_psd import factor_psd
+
     EXAMPLES:
 
     Create a symmetric positive-semidefinite matrix over the symbolic
@@ -241,6 +245,10 @@ def random_psd(V, accept_zero=True, rank=None):
     ``accept_zero`` is ``False``, we restart the process from the
     beginning.
 
+    SETUP::
+
+        sage: from mjo.cone.symmetric_psd import is_symmetric_psd, random_psd
+
     EXAMPLES:
 
     Well, it doesn't crash at least::
@@ -300,9 +308,8 @@ def random_psd(V, accept_zero=True, rank=None):
         # Use the one the user gave us.
         rank_A = rank
 
-    # Begin with the zero matrix, and add projectors to it if we have
-    # any.
-    A = V.zero_element().column()*V.zero_element().row()
+    # Begin with the zero matrix, and add projectors to it if we have any.
+    A = V.zero().column()*V.zero().row()
 
     # Careful, begin at idx=1 so that we only generate a projector
     # when rank_A is greater than zero.