Table of all possible irreps of Lie groups

Last weekend, I wrote a program in SAGE that list all possible irreps of a Lie group, one specified the group (in Cartan’s classification) and the maximum sum of the Dynkin labels. Check the notebook in here. Since I’m not a programmer, please feel free to leave comments, specially if you find ways to optimize [...]

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Review: Sage beginner’s guide.

Sage beginner’s guide is a book by  Craig Finch, published recently by PACKT publishing. After spending two weeks looking at different aspects of the book, I can say with property that this is an excellent book, an I’ll recommend it for beginners to medium experienced SAGE users. Since this is the first book I review, [...]

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Sage tip: Plots with shadow

No comments! It was beautiful p = plot(sin(x), (x,-5, 5), thickness=2, color=’red’) for n in xrange(1,20): p += plot((1-n/20)*sin(x), (x,-pi,0), thickness=0, fill=’axis’, fillcolor=’blue’, fillalpha=.01) p += plot((1-n/20)*sin(x), (x,0,pi), thickness=0, fill=’axis’, fillcolor=’gray’, fillalpha=.01) show(p, figsize=10,ticks=pi/3,tick_formatter=pi, fontsize=16) reset() var(‘x’) f(x) = sin(x) p = plot(f(x), (x,-5, 5), thickness=2, color=’red’) for n in xrange(1,20): p += plot(((n-1)/20)*sin(x), (x,-pi,0), [...]

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SAGE tip: More about Differential Forms

In a previous post we discuss the definition of the coordinated patch on a manifold, how to define differential forms, wedge them or calculate their exterior derivative… even simplify’em. This time a zero form will be defined and a list of forms will be created… So, let’s begin! Define a 0-form Once created the coordinated [...]

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SAGE tip: GRmodule. Day 07.

This code is supposed to be (if some one does the work in the future) located in sage.tensor.differential_form_element. The code presented below is a slight modification of Joris code for differential forms manipulation on SAGE. Needed modules from sage.symbolic.ring import SymbolicRing, SR from sage.rings.ring_element import RingElement from sage.algebras.algebra_element import AlgebraElement from sage.rings.integer import Integer from [...]

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