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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SAGE tip: Exponentiate a Matrix

From time to time when one works with operators, such as in Quantum mechanics, something like an exponential of the operator appears (this is also the case in many areas of Mathematics like group theory of differential geometry). This exponentiation of a matrix should be understood as the series expansion of the exponential. SAGE knows [...]

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