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 Socratic
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Jan
13
asked How to efficiently write code with many functions that have variable number of iterators/arguments/
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 $userInt, not harded-coded 3.
Jan
12
asked How to inject unevaluated list of Unique into a RuleDelayed?
Jan
11
accepted How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
Jan
11
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
Any ideas with Dt are welcome too! Thanks
Jan
11
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
Yes, differentials are w.r.t scalar. Also, so that it works with Series we need to define Derivative for higher order derivatives. My proposal is to replace your first line with the following two: Derivative[ndiff__][mydot][x__] /; And @@ Thread[Less[{ndiff},2]] := dmydot[ndiff][x]; and Derivative[ndiff__][mydot][x__] /; Or @@ Thread[GreaterEqual[{ndiff},2]] := 0;. Any thoughts?
Jan
10
awarded  Custodian
Jan
10
reviewed Approve Permutations[Range[12]] produces an error instead of a list
Jan
10
reviewed Approve Permutations and recurrence equation
Jan
10
reviewed Approve Why doesn't Compile work on the Permutations function with second arguments?
Jan
10
reviewed Reviewed How to abort on any message generated?
Jan
10
reviewed Looks OK Permuting symbols
Jan
10
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
@ShutaoTANG How do you define UpValues when mydot can be arbitrarily deep inside of an expression?
Jan
10
comment How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
I strongly prefer against injecting code into a built-in function like this: ClearAttributes[D, Protected]; D[expr_, args__] := Block[{$inD = True, result}, result = (D[expr /. mydot[seq___] :> NonCommutativeMultiply[seq], args]) /. NonCommutativeMultiply[seq___] :> mydot[seq]; result ] /; ! TrueQ[$inD] SetAttributes[D, Protected];
Jan
10
asked How to make `D` apply chain rule on user-defined symbols as it does on `Dot` and `NonCommutativeMultiply`
Jan
10
comment What is the recommended writing style for WDC pages?
@RonaldMonson I think this makes most sense. Thanks for your input.
Jan
10
revised What is the recommended writing style for WDC pages?
added 6 characters in body
Jan
9
asked What is the recommended writing style for WDC pages?
Jan
8
answered Chopping matrix elements, real or imaginary
Jan
8
answered How to find the derivative value at $(\pi,0)$ for this implcit function $n$ times?