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comment NDSolve - sampling for result during the computation
Have you tried [Mma's RandomVariate[...]](reference.wolfram.com/mathematica/ref/RandomVariate.html)? What does values do? Is there a reason you are using ExplicitEuler? You would benefit by letting Mathematica choose the solver automatically or use perhaps the magic-wand Method->"LSODA". Also, why not just let t range from 0 to a very large number (for long term behavior)?
Apr
20
comment How to solve this integral equation?
Could you share the numerical values of a, b, c and d? That may help.
Apr
20
comment Understanding of method for NDSolve
LSODA is similar to the LSODE (the "Livermore Solver for Ordinary Differential/Algebraic equations" or some such). It is composed of stiff and non-stiff methods which switch when stiffness is sensed. The LSODE itself uses the Adams-Moulton method for non-stiff regions and then switches to a variable step, variable order Backward Difference Formula (Euler's method, I think). You can find more information via google. The report by Hindmarsh is also available for download as a pdf file.
Apr
20
comment Shooting method
NDSolve is a good place to start. There are some good examples here on SE. The comprehensive section on Advanced numerical differential equation solving may be useful too. What does your equation simulate? Looks like some sort of a fluid dynamics equation. These are separate equations? They look stiff so when you do get around to NDSolve, I recommend using the LSODA method.
Apr
17
comment What are these strange shapes in my Plot3D[]?
@YungHummmma could you share your NIntegrate code?
Apr
17
comment What are these strange shapes in my Plot3D[]?
@YungHummmma Yes, I would suspect so.
Apr
16
comment What are these strange shapes in my Plot3D[]?
Are you plotting the result of an NDSolve operation? If that is the case, you are trying to perhaps probe a time step of your equation beyond the limits imposed by numerical stability/stiffness for the solver type being used. Conjecture, at best.
Apr
11
comment Solving a nonlinear, second order d.e. in Mathematica
@Funzies what was the error your received with NDSolve? I am trying to solve this with a stiff solver such as LSODA and I've been receiving an NDSolve::berr error
Apr
11
comment Solving a nonlinear, second order d.e. in Mathematica
@LeonidShifrin NDSolve stiffness, story of my life! I found that using Method->"LSODA". I let the "MaxDifferenceOrder" "float". Given your hightened understanding of this problem, do you have any comment on my positive experience with "LSODA"?
Sep
6
comment Modelling the effect of a structure on a “tsunami” (hyperbolic wave equation)
@Kuba Very interesting answer that was!
Sep
6
comment Modelling the effect of a structure on a “tsunami” (hyperbolic wave equation)
Very interesting! I'll see how this cranks out on my computer.
Aug
7
comment How to demonstrate lack of stability with advection equation
Why when I increase the MaxPoints while holding MinPoints constant, does the error increase? I would assume the reverse should happen...
Aug
7
comment How to demonstrate lack of stability with advection equation
Thank you. So is it difficult to back-out a "CFL" number out of this example when one uses mathematica since mma always "sets/adapts spatial grid resolution"?
May
13
comment Reversing the ColorScheme used in an ArrayPlot and setting the font size in the color bar
You might want to change rData to FData.. Thank you though, the essense of the answer still exists.
May
13
comment Reversing the ColorScheme used in an ArrayPlot and setting the font size in the color bar
Thank you. I would have never thought of this.
May
13
comment Reversing the ColorScheme used in an ArrayPlot and setting the font size in the color bar
How do I change the font size of the text in the colorbar? I was using BarLegend for that purpose... ArrayPlot[mat, PlotLegends -> BarLegend[{GrayLevel, {0, 1}}, LabelStyle -> {FontSize -> 20}]]
May
13
comment Reversing the ColorScheme used in an ArrayPlot and setting the font size in the color bar
@belisarius Mathematica 9.0... Will make the edit
May
10
comment Changing FrameTicks of ListPlot
@BoLe Useful! Thanks!
May
10
comment Changing FrameTicks of ListPlot
This is rather interesting. I didn't think that "specifying my data differently" outside the plot function would help me...
Apr
30
comment Contour heat graph (ListContourPlot?)
Aaah Mathematica 9!!! Your PlotLegends is now fixed.... it was so messed up in Mathematica 8.0