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1:eJxTTMoPCtZiYGAwtEr1qggJ8c0PcC6Nyo10d8yvzAvPL8zM8jUoLvHxCXR19DMudndytLUFAIyYD9M=
Insanity is doing the same thing over and over again and expecting different results. — Michael Scott
Be insane if absolutely necessary.
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6h |
comment |
How to asynchronously download 100000 urls in an efficient way "how to download 10000 urls in an efficient way?" — you use a different tool better suited for the job. |
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6h |
revised |
How can I understand the result Mathematica returns from DSolve? deleted 3120 characters in body; edited title |
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6h |
comment |
Where can I find description of errors and warnings? That's a warning that is pretty descriptive and complete. What more information were you expecting? |
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10h |
comment |
CUDAQ[] returns False in version 9 while true in version 8 I think you might have to force reinstall it... I had a similar issue when v9 first came out (I don't exactly recall what I did) |
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15h |
reviewed | Close Import/Export Cluster Object |
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1d |
awarded | Nice Answer |
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May 15 |
awarded | Nice Answer |
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May 15 |
comment |
How to plot filling under a curve? @Kuba I'll admit it might be a bit strange for a beginner, but it's documented. The plotting functions try to show the region that is "most interesting" (or the range where most of the y values are). For example, try this: Plot[Sinc[x] - Piecewise[{{Sin[x]/x, Abs[x] < 2}}, 1], {x, -2.01, 2}] with and without PlotRange -> All. It is up to the user to verify and modify according to their needs. Since each person's definition of "interesting" varies, I think this compromise is reasonable. Of course, those advocating for explicit options have nothing to lose, since you can still be explicit. |
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May 14 |
comment |
How to plot filling under a curve? @Kuba The simple explanation is that Show uses the options of the first argument, so sometimes the second one can get truncated if you don't pass the right options. |
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May 14 |
comment |
Concerning ShowLegend in Mathematica @l3win You are using old functions from the PlotLegends package, which xslittlegrass mentioned. If you want to use v9 functions, you'll have to translate them yourself to use the newer ones. Did you try loading it first to see what happens? (ignore the warning) |
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May 14 |
comment |
When using NMinimize[…,Method->“DifferentialEvolution”] is an “iteration” different than a “step”? An indicator that they're different: f[x_?NumericQ] := Sin[.4 x] + .7 Cos[.6 x] x;
{steps, eval} =
First /@ Last@
Reap[NMinimize[{f@x, -10 < x < 10}, {x},
Method -> "DifferentialEvolution",
StepMonitor :> Sow[{x, f@x}, "steps"],
EvaluationMonitor :> Sow[{x, f@x}, "eval"]], {"steps", "eval"}]; Plot[f@x, {x, -10, 10},
Epilog -> {{Red, Point[eval]}, {Green, Point[steps]}}] Also look at the lengths of steps and eval. |
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May 14 |
comment |
When using NMinimize[…,Method->“DifferentialEvolution”] is an “iteration” different than a “step”? @Adam That's why I asked for a minimal example, not your actual problem. It could just be the simplest "Hello world" of NMinimize that is sufficient to illustrate your problem. Regardless of whether it matters or not, it makes life simple for everyone who might answer your question if they can simply copy your code and run it to test it. Most of us don't have the time or inclination to get creative and think up of a valid function to minimize, appropriate conditions, etc — all of this before we actually get to the heart of your problem. |
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May 14 |
comment |
DAE - varying initial conditions @lambda1990 Please do not post comments as "answers". You should see a "Comment" link under Jonathan's answer, which allows you to reply to his answer. I've converted this one for you, but please remember the next time. |
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May 14 |
comment |
When using NMinimize[…,Method->“DifferentialEvolution”] is an “iteration” different than a “step”? Can't you Sow them and find out? (I don't know a lot about how this works, so I could be wrong). In any case, please include a minimal example (i.e., definitions for ssd, cons, vars, etc.) |
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May 14 |
comment |
How do I operate on a set of ordered pairs? I want to square each inidividual element of an ordered pair and then add it There are several options (and many variants have been asked before here)... the simplest: pairs /. {a_, b_} :> a^2 + b^2 |
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May 14 |
comment |
Finding areas of beings in microscopic image Wow, fantastic! |
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May 14 |
comment |
White noise $\eta(t)$ Nice, I think this is exactly what the OP was after. Perhaps you could also give this question a shot... |
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May 14 |
comment |
White noise $\eta(t)$ @richard Please still consider adding a minimal example so that someone can perhaps provide an answer using the new stochastic process functions in version 9 (or you can answer your own question as well). That way, it will also be of use to future visitors who have the same problem (I had forgotten as well and was reminded of the new functionality by Szabolcs's link) |
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May 14 |
comment |
White noise $\eta(t)$ If you write a 1 line question, you can only expect to get a 1 line answer which may or may not work. Please include more information in your question and a minimal example of what you're trying to do. I'm guessing you're trying to solve a stochastic DE, in which case you might have to look at other specific approaches and not NDSolve |
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May 14 |
comment |
White noise $\eta(t)$ Something like: η[_?NumericQ] := RandomReal@NormalDistribution[] ? |
