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| bio | website | |
|---|---|---|
| location | China | |
| age | ||
| visits | member for | 9 months |
| seen | 12 hours ago | |
| stats | profile views | 134 |
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Apr 9 |
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Putting NDSolve into ParametricPlot The reason is just, you use p0 = 1 in unforced while actually you use p0 = 0 in the last two lines… |
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Apr 8 |
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Removing zero values from ordered pairs I've added a snapshot to my answer. It seems that {_, 0} | {0, _} and {a_, 0} | {0, a_} are different… |
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Apr 8 |
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Removing zero values from ordered pairs OK, I forgot it completly ORZ… |
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Apr 8 |
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Removing zero values from ordered pairs Well, not really. The fastest seems to be DeleteCases[list, {_, 0} | {0, _}]. |
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Apr 8 |
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problem with Importing multiple files You can also refer to this solution :D |
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Apr 8 |
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Manipulating output from Solve Manipulate requires explicitly stating the dependent variables, then, why not explicitly stating the dependent? I guess something like f[H1_, H2_]=sol1[[1, 1]]; g[H3_, H4_]=sol2[[1, 1]]; Manipulate[ContourPlot[f[H1, H2] - g[H3, H4], {H1, a, b}, {H2, c, d}], {H3, e, f}, {H4, g, h}]
will work. |
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Apr 8 |
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NDSolve: Normalizing at every step Er… You mean you need to normalize y at the moment NDSolve gets the solution for the first time point and then solve the y at the next time point with this solution and so on? …Is it still a PDE-solving issue? |
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Apr 7 |
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Help solving a systemClear[r] first and then run your code. |
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Apr 7 |
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BC for transport equation using NDSolve @Spawn1701D Yeah, f[10, t]==0 is still approximate, but I think for numeric solution it's acceptable, since it's hard to find a better BC… For this part I've edited my answer a little. |
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Apr 3 |
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How to plot a 3D surface with a simple black and white style? In fact, Lighting -> {White} is enough. |
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Mar 28 |
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Mathematica envelope for the bottom of a plot, a generic function This method is good！ but… why does the 1.4 standard deviation work? I mean… what's the theoretical basis of this method? |
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Mar 9 |
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Numerically solving an inhomogeneous partial differential equation Oh, I see, it's symmetric and smooth at $r=0$, right? Now I can understand it both by considering $y$ as a steady state of something like heat distribution and considering the Cartesian form of the equation. |
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Mar 8 |
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Numerically solving an inhomogeneous partial differential equation Er…why does $\frac{1}{r}y^{(1,0)}(r,z)$ become $y^{(2,0)}(r,z)$ when $r\rightarrow 0$? |
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Mar 7 |
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Solving and plotting ODEs while varying one of the initial conditions @ruebenko Wow, I think I'd better upgrade to v9 quickly. |
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Mar 7 |
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Solving and plotting ODEs while varying one of the initial conditions Your equation can be solved analytically, so you can just exchange y[1]==1 with y[1]==z and DSolve the equation and Plot3D[x[t] /. sol, {t, -1, 1}, {z, -1, 1}]. |
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Feb 28 |
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How can I fill an entire Building with transparent points? @subbu Yeah, that'd be easy to fix, but I think can now go to bed without another edit since you've already understood :D. |
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Feb 28 |
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How can I fill an entire Building with transparent points? @subbu See my edit for the answer. |
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Feb 28 |
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How can I fill an entire Building with transparent points? @subbu You mean you've already got 10000 specified points and you want to test if they are inside the building and remove the ones outside? |
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Feb 28 |
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Fourier transformation of solution of differential equation Oh, that's interesting! |
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Feb 28 |
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Fourier transformation of solution of differential equation But an analytical Fourier transform for the function seems to be still impossible? |
