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15h
comment What's wrong with naming a rule?
Yes I find this very confusing. I think I fall somewhere between "beginner" and "experienced", and I find weird nuances in Mathematica like these only serve to confuse people like me. I really wish they implemented a global switch that turned off all "noob" features to make Mathematica behave more regularly.
1d
comment What's wrong with naming a rule?
@ciao that doesn't explain why % works.
2d
comment CompiledFunction::cfsa Argument x at position1 should be a machine-size real number
please format your mathematica code by setting them in `. Also, what is the body of the the Compile function?
Apr
28
comment How to make a replacement, provided an inner rule applies
I came up with another way to do it (posted as an answer); can you see if it is a viable alternative that prevents double traversal?
Apr
28
comment Why are CoefficientRules and MonomialList so slow?
What version of Mathematica are you using? On v8, my computer takes 270 seconds to finish CoefficientRules[Expand@#,y]& (but only 1 second to do the first two). Timings on v9 are similar to yours. On v10.3, it takes 15 seconds to do first three (regression?) on 10.4 it takes 17 seconds on the first three (further regression).
Apr
28
comment About Pade approximants for higher degrees using Mathematica
Please format your question properly. You can phrase your question in terms of x, y, z... Instead of alpha, beta, gamma...
Apr
27
comment Mathematica Serious Startup Error
I would also suggest contacting Wolfram support (wolfram.com/support/contact)
Apr
26
comment Subscripted variables give errors in Module expression
When I first started using Mathematica I used subscripts. Eventually I realized this is not a good way to go. I'd recommend switching to unsubscripted variables (like Ω1 instead of Subscript[Ω,1]).
Apr
26
comment How to construct the RHS of Wick's theorem
ScalarQ seems to be undefined
Apr
26
comment Is there an internal logic behind short form symbols, such as @ (Prefix), @@ (Apply), /@ (Map), /. (ReplaceAll)
~ Infix .................
Apr
24
comment How to construct the RHS of Wick's theorem
@DanielLichtblau I'm not seeing exactly which subsection I should be looking at. My question is closer to constructing an expression rather than doing algebra.
Apr
24
comment How to construct the RHS of Wick's theorem
@evanb Yes, please post whatever it is; any hints would be helpful.
Apr
24
comment How to construct the RHS of Wick's theorem
@evanb I'd like the result of the NCSort[input]//Expand given above which is basically the RHS of Wick's theorem. Note however, only the contractions required to sort the input appear and not all of them.
Apr
22
comment How do I use the third and fourth arguments of Parenthesize?
The third argument seems to work properly not with an Integer but with Plus, Times or Power. I can't seem to find other Heads one can use in the third argument.
Apr
22
comment How do I use the third and fourth arguments of Parenthesize?
Do you mean to check docs for PrecedenceForm? I think you're right about the third argument.
Apr
22
comment `Series` acts on variables outside its argument?
I really don't understand your question. Are you just trying to compute $f(h)_\text{exact} - f(h)_\text{taylor}$? In that case you should be using f[h] - Series[f[h + δ], {δ, 0, 2}]
Apr
21
comment How do I use the third and fourth arguments of Parenthesize?
@kglr did you forget to finish your comment?
Apr
21
comment Proving that Reverse[Reverse[x]]]=x
I think this is the reason the developers introduced Inactive in version 10: so that symbols like Reverse can be deactivated for symbolic manipulation. Do you agree with my comment to OP?
Apr
21
comment Proving that Reverse[Reverse[x]]]=x
Reverse is an active function. There is no built-in symbolic representation of Reverse upon which analysis can be carried out. I have found that you can use Mathematica's analysis capabilities on symbols which in the documentation are noted as being "suitable for symbolic manipulation."
Apr
17
comment Dynamica Package for Mathematica
It won't download for me either; you should definitely contact the authors.