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Gianluca Gorni
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Hello Gianluca Gorni, Thank you for your help. Yeah, I have a reason to think that there are multiple solutions to my equations ignoring periodicity. The source of the two equations is This one: \$sin(x)cos(\epsilon k) + sin(\epsilon...
You can do a lot this way: sol = NDSolveValue[{D[r[t], t] == (r[t].r[t])^-1 RotationMatrix[Pi/2, {0, 0, 1}].r[t], r[0] == {1, 1, 1}}, r, {t, 0, 1}] sol[1]
The solution set is more complicated than that: Reduce[(js + ps) 6 == w && js (pd + 5) == w && ps pd == w, Reals] // LogicalExpand I don't know the exact reason why Solve gives an empty set in that special case, but with slight...
The code pp/.Line[x_]:>{Arrowheads[Table[.04, {4}]], Arrow[x]} targets the hidden internal structure of the output of Plot and ParametricPlot. Try Plot[x,{x,0,1}][[1]] you will see that it contains a Line primitive, which...
Bill, Thank you, an interesting idea, though I am not too sure how to interpret the output in relation to my problem.
Yup, exact way to do it! ![enter image description here][1] [1]: https://community.wolfram.com//c/portal/getImageAttachment?filename=ScreenShot2021-04-09at1.40.17PM.png&userId=524853
Thanks so much!
Aha! Thank you!!
Maybe the wireframe version is clearer: Plot3D[2 x^2 y/(x^4 + y^2), {x, -1, 1}, {y, -1, 1}, PlotPoints -> 200, Exclusions -> Automatic, MeshFunctions -> {#2/#1 &}, Mesh -> {Tan[Pi/2 Range[-19, 19]/20]}, PlotStyle -> None]
The solution uses complex numbers, but its values are real and correct: sol1 = DSolveValue[{eq, i[0] == i0}, i, t] FullSimplify[{eq, i[0] == i0} /. i -> sol1] Block[{\[Gamma] = 1, \[Mu] = 1, \[Lambda] = 1, i0 = 1}, ...