X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=mjo%2Fcone%2Fschur.py;h=1fa1e52407fe2782b3852cf1482970724abb2003;hb=07d8d3f5ce02c2d2693244d541561f264b5037c7;hp=88b7d82722956f73a54ac429641c7143df99b749;hpb=c7572b7c827ee6ee604236c38a328ac69a3a7a2a;p=sage.d.git diff --git a/mjo/cone/schur.py b/mjo/cone/schur.py index 88b7d82..1fa1e52 100644 --- a/mjo/cone/schur.py +++ b/mjo/cone/schur.py @@ -7,7 +7,8 @@ from sage.all import * def schur_cone(n, lattice=None): r""" - Return the Schur cone in ``n`` dimensions. + Return the Schur cone in ``n`` dimensions that induces the + majorization ordering. INPUT: @@ -64,11 +65,10 @@ def schur_cone(n, lattice=None): [GourionSeeger]_, whose elements' entries are in non-increasing order:: - sage: set_random_seed() sage: n = ZZ.random_element(10) sage: K = schur_cone(n).dual() sage: x = K.random_element() - sage: all( x[i] >= x[i+1] for i in xrange(n-1) ) + sage: all( x[i] >= x[i+1] for i in range(n-1) ) True TESTS: @@ -80,10 +80,9 @@ def schur_cone(n, lattice=None): The Schur cone induces the majorization ordering:: - sage: set_random_seed() sage: def majorized_by(x,y): ....: return (all(sum(x[0:i]) <= sum(y[0:i]) - ....: for i in xrange(x.degree()-1)) + ....: for i in range(x.degree()-1)) ....: and sum(x) == sum(y)) sage: n = ZZ.random_element(10) sage: V = VectorSpace(QQ, n)