dearN
  • Member for 9 years, 11 months
  • Last seen more than a month ago
Running an initialization cell on Mathematica start up
Accepted answer
17 votes

I think I found it but I'd be more than happy to look at other alternatives if any provided: Shift + Ctrl + O to open Options > Notebook options > Evaluation options > Global preferences from the ...

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Small random disturbance of a flat surface
5 votes

Vitaly's answer is correct in that it fantastically produces a splined random disturbace surface. However, I was unable to use it as an initial condition for my NDSolve[...]. Based on whuber's ...

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Precision of number not maintained when saved via Export
5 votes

Replacing N[a] with SetPrecision[a,5] helped. The above answer by Fred Daniel Kline helps too but isn't really what I am looking for.

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Numerical solution of a differential equation with NIntegrate coefficients
2 votes

First solve this: a = NIntegrate[Sqrt[1 + E^tt^2 Sin[tt^2]], {tt, 0, 1}] And then do this: DSolve[{D[u[t], t] == a u[t], u[0] == 1}, u[t], t] That should solve the problem.

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Second Order Non Linear Differential Equation
2 votes

This problem seems to be really stiff as whuber has pointed out. Using the BDF method and allowing NDSolve to ruminate about the order, didn't quite change the solution (z value where stiffness was ...

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Problems with NDSolve and stiffness
1 votes

As prompted by one of the comments, stiffness switching did help some. I usually go with Method->LSODA for stiff equations but tried Method -> {"StiffnessSwitching", Method -> {"...

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Trying to use NDSolve to solve Blasius equation
1 votes

As late as this answer may be: sol = NDSolve[{f'''[η] + 0.5 f[η] f''[η] == 0, f[0] == f'[0] == 0, f'[10] == 1}, f, η] Plot[f[η] /. First[sol], {η, 0, 10}] Plot[f'[η] /. First[sol], {η, 0, 10}] ...

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Replacing variable in an equation with an Interpolating function polynomial and plotting residual
1 votes

Faculty members at our math department tell me that this (below) is a more traditional way of plotting the residual. Apparently I wass a little off with my interpretation of the residual. "The ...

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Mathematica showing error for NDSolve
-1 votes

Perhaps this is a possible answer: Clear[a, b, c, tMax, x, t]; tMax = 20; sol = ParametricNDSolveValue[{x''[t] + c*Sin[x[t]] == 0, x'[0] == 0, x[0] == 2.96706}, x, {t, 0, tMax}, {c}] Plot[...

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