sage-5.1.beta4 released

[Jeroen Demeyer]

Dear Sage lovers,

We're releasing Sage 5.1.beta4.

Source archive:

http://boxen.math.washington.edu/home/release/sage-5.1.beta4/sage-5.1.beta4.tar

Upgrade path:

http://boxen.math.washington.edu/home/release/sage-5.1.beta4/sage-5.1.beta4/

== Tickets ==

* We closed 143 tickets in this release. For details, see

http://boxen.math.washington.edu/home/release/sage-5.1.beta4/tickets.html

Closed tickets:

#8151: wrong file permissions in lie-2.2.2.p3.spkg [Reviewed by Keshav Kini]
#9950: Oriol Castejon: Change Brian package from experimental to
optional [Reviewed by Karl-Dieter Crisman]
#11433: Mike Hansen: Move graphviz-2.16.1.p0.spkg from optional to
experimental [Reviewed by Benjamin Jones]
#12983: Keshav Kini: Fix LiE optional SPKG [Reviewed by R. Andrew Ohana]

Merged in sage-5.1.beta4:

#6812: Nicolas Borie, Simon King: Enumerate integer vectors modulo the
action of a Permutation Group [Reviewed by Karl-Dieter Crisman, Simon
King, Nicolas Borie]
#10514: Douglas McNeil: legend_label doesn't work when plotting multiple
functions at the same time [Reviewed by Karl-Dieter Crisman]
#10678: Dan Drake: properly link "derivative" in
sage.symbolic.expression.derivative documentation [Reviewed by Benjamin
Jones]
#11155: Alexei Sheplyakov, Titus Nicolae: abs(pi+I) = pi+I [Reviewed by
Burcin Erocal]
#11311: Franco Saliola, John Palmieri: engine="pdflatex" in view is
ignored [Reviewed by Karl-Dieter Crisman, Franco Saliola, John Palmieri]
#11608: Rob Beezer: RDF/CDF eigenvalues: symmetric matrices,
multiplicities [Reviewed by Volker Braun]
#11888: Benjamin Jones: Sage is missing the lambert_w function [Reviewed
by Keshav Kini, Karl-Dieter Crisman, Fredrik Johansson, Burcin Erocal,
Douglas McNeil, William Stein]
#11951: Douglas McNeil: nth_prime is badly documented [Reviewed by
Karl-Dieter Crisman]
#12076: Mike Hansen: sage-location doesn't deal with packages after
initialize_pkgconfig_files has run [Reviewed by Dan Drake, Karl-Dieter
Crisman]
#12195: Robert Bradshaw, Rob Beezer, William Stein: numerical_approx
broken for vectors [Reviewed by Rob Beezer, William Stein, Dan Drake]
#12345: Douglas McNeil: Sympy minus infinity doesn't convert to Sage
[Reviewed by Karl-Dieter Crisman]
#12671: Punarbasu Purkayastha: attaching files which have spaces in
absolute path name fails on second run [Reviewed by William Stein]
#12756: Jeroen Demeyer: interrupt.pyx test: flush buffers before fork()
[Reviewed by Volker Braun]
#12789: Jeroen Demeyer: Move local/bin/sage-check-64 to
spkg/bin/sage-arch-env [Reviewed by Volker Braun]
#12798: Punarbasu Purkayastha, Karl-Dieter Crisman: list_plot3d plots
extraneous points at z=0 and doesn't take color or rgbcolor as keywords
[Reviewed by Karl-Dieter Crisman, Punarbasu Purkayastha]
#12813: Antonio Russo: contour_plot region option [Reviewed by Jason
Grout, Karl-Dieter Crisman, Jeroen Demeyer]
#12971: Nathann Cohen: Biggs-Smith graph [Reviewed by Keshav Kini]
#12980: Nathann Cohen: Harries-Wong graph [Reviewed by Keshav Kini]
#12981: Nathann Cohen: Ljubljana Graph [Reviewed by Keshav Kini]
#12999: Keshav Kini: Color('red') > Color('red') returns True [Reviewed
by Karl-Dieter Crisman]
#13006: Dan Drake: All-paths in a graph blows up when start and end are
identical vertices [Reviewed by Rob Beezer, William Stein]
#13009: Dan Drake: Add blank lines for a couple plots in reference
manual [Reviewed by Karl-Dieter Crisman]
#13018: Rob Beezer: Positive definite check for exact matrices [Reviewed
by Dan Drake]
#13023: Andrey Novoseltsev: Move toric varieties to a dedicated folder
[Reviewed by William Stein]
#13030: Robert Bradshaw: Use pxd file for pynac declarations [Reviewed
by Mike Hansen]
#13095: John Cremona: Update Cremona's table of elliptic curves to
240000 [Reviewed by R. Andrew Ohana]