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Feel free to correct the grammar mistakes in my posts.


Nov
17
comment How to get a more compact form of this probability calculation?
I think your program is wrong. In your program, a3 and a4, s4 and s5 are independent, but actually they're not, a3 is part of a4, s4 is part of s5!
Nov
17
comment How to solve this probability symbolically or numerically?
@hengxin You can use FindSequenceFunction: FindSequenceFunction[Table[(μ^m (2 λ + μ))/(2^(m + 1) (λ + μ)^(m + 1)), {m, 5}], m]
Nov
15
comment Calculating integral by Romberg Algorithm
I'm not surprised that @DanielLichtblau is confused. It'll be better to keep your original code in the question.
Nov
15
comment Calculating integral by Romberg Algorithm
@ShutaoTang Oh, I should have read the document of Flatten more carefully. Thanks for pointing out.
Nov
14
comment How to extract a list of available Method-s
possible duplicate of How do I get a list of allowed values for an option?
Nov
14
comment Calculating integral by Romberg Algorithm
@ShutaoTang Oh, I think that besides some minorities, Chinese always put family name ahead. For your new question, you should notice that InputForm and PrintPrecision and NumberForm etc. Only control the display of the number, it doesn't influence Precision nor Accuracy. Nevertheless, calculate with MachinePrecision and control the display with NumberForm etc. may be more close to what your text book has done, significant arithmetic is the secret recipe of Mathematica anyway.
Nov
13
comment Series expansion of InterpolatingFunction obtained from NDSolve
Method -> {"FixedStep", Method -> {"ImplicitRungeKutta", "DifferenceOrder" -> 5}} is also available, there should be more, I guess.
Nov
13
comment Series expansion of InterpolatingFunction obtained from NDSolve
Seems that InterpolationOrder in NDSolve can only be set to All.
Nov
11
comment What is the best way to flatten a linked list with lists as values?
@Mr.Wizard Yeah, they all display as intended.
Nov
11
comment What is the best way to flatten a linked list with lists as values?
What font do you use? The AngelBracket simply doesn't display correctly in my browser.
Nov
10
comment Is it possible to pipe the output of EvaluationMonitor to Excel?
Well, are you sure it's the same region?: Column@{RegionPlot[x^2 + y^2 < 0.2828427 && 0.1 < x < .2 && 0.1 < y < .2, {x, 0, 0.2828427}, {y, 0, 0.2828427}], ParametricPlot[{r Cos[\[Theta]], r Sin[\[Theta]]}, {r, 0.1, 0.2828427}, {\[Theta], 0.0, \[Pi]/2}]}
Nov
6
comment A Stupid Question Maybe - EigenNDSolve
In fact you can consider modifying the source code a little. (Add a Rationalize[……, 0] somewhere etc. )
Nov
5
comment Poisson PDE using FDM in Mathematica
Well, if you don't add @xzczd in your comment, I won't get the reminder. BTW, your new-added code is messy (and in fact broken), please press Ctrl+Shift+I to change it into InputForm before pasting it here.
Nov
5
comment A Stupid Question Maybe - EigenNDSolve
"It may be that floating point numbers should not be input as such", this explanation isn't wrong, and I think the failure will be reproduced in any version of Mathematica. To fix the problem, the easiest way is to change the floating point numbers into exact numbers i.e. change 10.5 etc. to 105/10 etc.
Nov
3
comment Problem with series expansion and integrate
@rhermans Apparently it's not available for OP, one needs at least 75 reputations to start a bounty 囧.
Nov
3
comment Fluid mechanics problem concerning flow over a wedge
If you feel satisfied with an answer, you can click the checkmark sign to accept it.
Nov
1
comment Poisson PDE using FDM in Mathematica
@wlkyr So the polar form isn't what you need either and you simply want to explore FDM for irregular region?
Nov
1
comment Poisson PDE using FDM in Mathematica
Well, is it necessary for you to use FDM rather than NDSolve solving this equation? To say at least, is it necessary for you to use Cartesian form of the equation rather than polar form? The handling for irregular mesh in FDM is really cumbersome in my view, in fact that's where I stoped my self-learning for FDM. (You may be interested in this post. )
Nov
1
comment Division by zero is slow
@wxffles I think the most probable obstacle for one to understand the code is unfamiliarity with Unitize and vectorization :) …OK, I've added a bit explanation, just a bit though.
Nov
1
comment Aligning the axeslabel in a 3D list plot ($x,y,z$) (edited)?
@SeyhmusGüngören Sorry, I can't understand what you mean, I just checked my approach with kguler's data, the behavior is exactly the same at least in my computer. Can you elaborate a little?