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3h
comment Change Temporary Directory
Um, that's what I said...
4h
comment Is there a summation notation for the sum of products made two by two?
Is this a question about standard mathematical notation or about how to write code in the software system Mathematica to represent such a sum?
4h
reviewed Close Is there a summation notation for the sum of products made two by two?
4h
comment Higher-order, nonlinear differential equation with Initial Values
@GeorgeZhang Does the new answer do what you desire?
5h
revised Why does my code produce NDSolveValue::ndnum?
Formatted Greek letters
10h
comment DSolve will not apply assumption `m ∈ Integers`
@Nasser Functions called by DSolve use $Assumptions (Simplify, Refine, Integrate etc.), but otherwise I don't think DSolve uses it. I think DSolve gets stuck trying to figure out how to reduce the problem to integrals.
11h
revised DSolve cannot solve for certain branches of the solution
Updated for V10
12h
reviewed Leave Closed Why doesn't this pattern work?
13h
answered Accessing Reduce from DSolve
13h
answered Higher-order, nonlinear differential equation with Initial Values
16h
answered Change Temporary Directory
16h
comment Difference between double quotes
There are a lot of quotation marks in Unicode, and Mathematica will treat them as distinct, unless they are translated to the ASCII double quote when copy-pasted.
16h
reviewed Reviewed Rotate points by 60° in 2D
16h
comment Rotate points by 60° in 2D
This question can perhaps be answered without the code, but as a courtesy to those who would help you, it is customary when you have code that does not work to post the code as text instead of an image.
17h
comment Rotate points by 60° in 2D
Welcome to Mathematica.SE! I suggest the following: 1) As you receive help, try to give it too, by answering questions in your area of expertise. 2) Read the faq! 3) When you see good questions and answers, vote them up by clicking the gray triangles, because the credibility of the system is based on the reputation gained by users sharing their knowledge. Also, please remember to accept the answer, if any, that solves your problem, by clicking the checkmark sign!
17h
comment Superscript prime symbol
Trying the first two lines, I get a Notation::noexbtag error. (V10.0.1)
18h
reviewed No Action Needed Superscript prime symbol
18h
comment Extracting coefficients from a power series
Yes, I think we do, but I don't know what's happening with the timing. I can now sometimes get my code to take 9.5 sec and sometimes I can get yours from the comment to take 3.5. I think they should be roughly the same, the major computation being the series, which is the same in both. Accessing the coefficients one at a time in your Table is less efficient than the vectorized approach in my answer, but the order of magnitude is 10^-5 sec per access, which is negligible compared to 3-10 sec. Not worth figuring out, really. Have a good day. :)
20h
comment Extracting coefficients from a power series
... Your new code for s does not match the definition in your answer; the new code takes advantage of the cacheing of Series results by computing the Series only once for m = 320, which is more or less what my answer does. I'm not sure what the reason for the big difference in timing. The old code in your answer recomputes the series for m = 0, 1,..., 320, if we go up to 320. That is a much slower approach.
20h
comment Extracting coefficients from a power series
@Dr.WolfgangHintze It takes 9.5 sec to evaluate the definition of s[m_] in your last comment plus 0.0029 sec to evaluate the table tW. Mine takes only 3.45 sec this morning (I'm sure it was taking much longer yesterday), but I repeated it. The time to compute s[m_] is significant and must be included in the total, as that is where the principal computation occurs. So yours is about 2.8 times slower....cont'd