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10h
comment How to create 'help' `?` for a function (as documentation)
It is safe to say that Mathematica's ::usage and template system is best described as "kludgy". For the benefit of others I provide a link to a question that summarizes the various problems and possible workarounds: mathematica.stackexchange.com/questions/58669/…
14h
comment How to define a complicated function inside the body of Compile?
If you define bigNastyFunction = Function[{y}, Sin[y]] instead of using Compile, then ByteCount[f] goes down from 11704 to 4560, the same as @MichaelE2 's first answer.
Feb
4
comment What's the easiest way to remove overall factors from polynomials?
What is keepVars supposed to be? Do I put x in there? Comment: the most essential thing for my application is only to drop powers of x. Dropping of constants is only for cosmetic reasons. Since you say the second part is not "well defined", would it be easier to code it with this relaxed request?
Feb
4
comment What's the easiest way to remove overall factors from polynomials?
@Dr.belisarius I didn't mean to use "trailing function character" as a technical term. I'm just saying that I'm not adding it for certain reasons.
Feb
3
comment Euler-Maclaurin summation
I think the missing $\gamma$ comes from the 'remainder' term of the Euler-Maclaurin formula.
Jan
29
comment How to organize expression by symbols (like Collect), but apply different functions to each coefficient
@Mr.Wizard ive been traveling, then got sick... Will come back when I get better
Jan
15
comment No help from ?-command
The bug is present in 10.3.1 The bug usually appears after I build documentation files using Workbench.
Jan
14
comment Add up data values for matching entries
@Mr.Wizard Your answer makes it clear my question is a duplicate of 4332. The OP of that question used a data set with all numbers, and as a result it wasn't immediately clear to me that he wanted to do the same thing I wanted to do.
Jan
14
comment Wrong result of simple math calculation. Is it possibly a bug of the program?
Read this: reference.wolfram.com/language/tutorial/NumbersOverview.html
Jan
12
comment How to inject unevaluated list of Unique into a RuleDelayed?
I messed up the code a bit. The upper limit of the Table iterator should be $userInt, not harded-coded 3.
Jan
11
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
Any ideas with Dt are welcome too! Thanks
Jan
11
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
Yes, differentials are w.r.t scalar. Also, so that it works with Series we need to define Derivative for higher order derivatives. My proposal is to replace your first line with the following two: Derivative[ndiff__][mydot][x__] /; And @@ Thread[Less[{ndiff},2]] := dmydot[ndiff][x]; and Derivative[ndiff__][mydot][x__] /; Or @@ Thread[GreaterEqual[{ndiff},2]] := 0;. Any thoughts?
Jan
10
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
@ShutaoTANG How do you define UpValues when mydot can be arbitrarily deep inside of an expression?
Jan
10
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
I strongly prefer against injecting code into a built-in function like this: ClearAttributes[D, Protected]; D[expr_, args__] := Block[{$inD = True, result}, result = (D[expr /. mydot[seq___] :> NonCommutativeMultiply[seq], args]) /. NonCommutativeMultiply[seq___] :> mydot[seq]; result ] /; ! TrueQ[$inD] SetAttributes[D, Protected];
Jan
10
comment What is the recommended writing style for WDC pages?
@RonaldMonson I think this makes most sense. Thanks for your input.
Jan
8
comment How to find the derivative value at $(\pi,0)$ for this implcit function $n$ times?
Maybe Dt (total derivative) is what you need to take implicit derivatives? You could also write y as y[x], put everything in one side of the equation, and call Series.
Jan
8
comment How to program efficient undershoot/overshoot
@can It's the small x behavior of the solution at x=x0. I can't start integration right at x=0 because that is a singular point.
Jan
8
comment $x^6-2\varphi^5x^5+2\varphi x+\varphi^6=0$ solving in radicals
I have no idea. I thought you would know...
Jan
7
comment $x^6-2\varphi^5x^5+2\varphi x+\varphi^6=0$ solving in radicals
Maybe cross-list this question with math.stackexchange.com?
Jan
4
comment Correct behavior of Integrate involving logarithmic cut, or possible bug?
@DanielLichtblau Then instead of releasing versions of Mathematica with garbage functions like ReIm and AllTrue, maybe they focus their attention on Integrate. Ok, that made me feel better.