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This package is no longer available in recent Mathematica versions. It has been replaced with builtin functionality. Please read here: http://reference.wolfram.com/language/Compatibility/tutorial/Geometry/Rotations.html


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is there some way to take the call ReplaceAll[var, rules]and make it forget contexts for a minute? BeginPackage["Test`"]; replace::usage = "Returns var/.rules."; print; Begin["`Private`"]; replace[rules_] := ReplaceAll[Symbol[$Context <> "var"], rules] End[]; EndPackage[]; Not general, but works. I would expect that replace[rules_] := ...


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You can make use of Formal Symbols. BeginPackage["Test`"]; replace::usage = "Returns \[FormalV]/.rules."; Begin["`Private`"]; replace[rules_] := \[FormalV] /.rules End[]; EndPackage[]; Then in the notebook. replace[\[FormalV] -> 0] (* 0 *) Hope this helps.


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Try replace[rules_] := ReplaceAll[Global`var, rules] in your function. Then replace[var -> 0] replace[Test`Private`var -> 0] yields 0 var as I think you'd like.


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As Compatibility/tutorial/Utilities/FilterOptions says: The functionality of FilterOptions is provided by the kernel function FilterRules. Although the syntax is not identical. You have to change two things in the code: BeginPackage["RiemannSum`", {"Utilities`FilterOptions`"}] to BeginPackage["RiemannSum`"] And Begin["Private`"] to ...


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ParametricNDSolve will return a numerical ODE solution with any number of free parameters. This parametric solution can then be fed into NonLinearModelFit (or whatever home-brew chi-squared algorithm you want to cook up) to find the best-fit values for the parameters. As an example, suppose we want have the ODE $y''(x) = - y(x)$, with initial conditions ...


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we can do a STFT of Sin[Pi*t^4] f[t_] := Sin[Pi*t^4]; data = Table[f[t], {t, 0, 5, 0.001}]; Spectrogram[data, SampleRate -> 1000] the instantaneous frequency of f[t] is $$\frac{\frac{\partial f(t)}{\partial t}}{2 \pi }$$.So the ideal instantaneous frequency is: Plot[Evaluate[D[Pi*t^4, t]/(2 Pi)], {t, 0, 5}] Ok,Combine the two image: Well ...



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