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I am trying to reproduce some results that were originally generated by a Fortran package that executed on a CDC 7600 mainframe (back in the late 1970s). The results are obtained by summing a large number (up to 15000) rapidly oscillating terms in...
By accident I have 'turned on' Link Snooper. Is there anyway to undo this? Under Evaluation, I can Quit a local kernel but not LinkSnooper. Even if I shutdown MMA and restart it, the Notebook title still has LinkSnooper appended. Many thanks...
I am trying to evaluate a sum over a large number of terms, each of which includes a Legendre polynomial. At fairly low numbers of the order parameter, I get enormous values for the polynomial. I have created a simple Notebook to illustrate the...
I am running 13.1 on a MacBook under Big Sur 11.7. On two occasions, the software crashes on launch with error code 814. This error persisted for several days, and it seemed to be resolved by an update for Safari, but this may have been a...
I am just starting to work with tensors such as the electromagnetic field tensors. I would like to write functions whose names indicate whether the tensor is contra variant, covariant or of mixed type. I can do this for some instances but not for the...
I am working my way through a book called The Geometry of Special Relativity and am at a stage where I want to define a time unit vector that has the property that its dot product with itself is -1. The dot product between space like unit vectors...
I apologize for the trivial nature of this question but my early attempts to seek an answer via the Community search engine just takes me to topics about creating Mathematica User Groups. I am starting to teach myself the elements of Group Theory...
I am trying to obtain the scalar product of two vectors whose components are complex valued. I can do the maths (as I understand it) by hand for my first simple examples but struggle with Mathematica 11. The simplest task which is to establish the...
I have just installed MMA-11 on my MacBook and the very first reactions I have, on a most trivial level, are these (and I cannot resolve them myself obviously): [1] The dock icon has changed from a cool(-ish) spiky sphere to a Simpsons like...
I am running MMA 10.4.1 under Mac OSX 10.11.5 and have started seeing some issues with drawing graphics inside a notebook as part of its documentation. Two examples of the problems I am seeing are: 1) I change the colour of a line from red to...