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If you have not had a course in GR before nor a firm grounding in differential geometry (tensor calculus), then I strongly recommend Thomas Moore's excellent book A General Relativity Workbook, University Science Books, 2013, ISBN 978-1-891389-82-5, ...
I have taught Physics 220 - Undergraduate Computational Physics at the University of Maryland, Baltimore County (UMBC) for over ten years. The course teaches the use of Mathematica to solve problems in physics.
I just installed 10.1. When I executed, it immediately popped a window to ask me for the location of MathLink. There is no such .exe on my computer. I think 10.1 is not yet ready for prime time.
Check out http://www.wolfram.com/mathematica/pricing/industry-individuals.php?desktop My guess is that the $300 price is sufficient for your needs, unless you anticipate making a lot of use of either Wolfram Alpha or the cloud.
Hi Dave, My guess is that the denser regions are in the plane of the galaxy.
Rather than using Needs["DifferentialEquations`InterpolatingFunctionAnatomy`"]; you can just simply use domain = sol[[1,1,2,1]] Kevin
Rather than doing an interpolation followed by an FFT, I encourage you to investigate the Lomb-Scargle approach. This will give you a periodogram without interpolation and the additional errors that involves. Google should help. Also, this book isn't...
My issues seem to have been cleared up in 10.0.2.
Yes. It handles them, and prints them so they look right and it can show either the symbolic form, or actually carry it out if you have specified things like the metric tensor, etc. It can also handle Einstein summations. I could send you a notebook...