I'm reading a book on general relativity, and the author makes a statement giving a proof that I don't find convincing. Suppose we wish to construct a scalar R (i.e. R(x') = R(x) under coordinate transformations) from the metric tensor and two powers of differentiation. That is, R must consist of terms of the form (∂∂g) and (∂g)(∂g). The claim is that R must be the scalar curvature, except for a multiplicative constant. Can someone point me to a proof? The importance of this result is that the Einstein-Hilbert action for the dynamics of spacetime is then uniquely determined. Well, unique in the absence of the cosmological constant. -- Gene
Is it just my imagination, or is Mathematica syntax between 5 and 100 times as clunky as it needs to be? Sometimes I feel it's like programming with Cobol^Cobol. --Dan
Can you give some examples, along with what you might consider preferable? I agree with you that hyperbole is literally the best thing *ever*. On Thu, Aug 14, 2014 at 3:14 PM, Dan Asimov <dasimov@earthlink.net> wrote:
Is it just my imagination, or is Mathematica syntax between 5 and 100 times as clunky as it needs to be?
Sometimes I feel it's like programming with Cobol^Cobol.
--Dan _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
-- -- http://cube20.org/ -- http://golly.sf.net/ --
Yes, I have one (among many) examples : FractionalPart, instead of Frac, grrr. or worst : ImplicitRungeKuttaLobattoIIIBCoefficients I agree to say that it is like cobol^cobol. But the engine is fast and some pieces of code within the core are pretty neat. I use maple with a strong canadian accent, pari-gp, mpmath and mathematica when everything else fails. best regards, Simon Plouffe
I guess we should be grateful that, by some oversight, it isn't ImplicitRungeKuttaLobattoRoman_ThreeBeeCoefficients --Dan On Aug 14, 2014, at 11:37 PM, Simon Plouffe <simon.plouffe@gmail.com> wrote:
Yes, I have one (among many) examples : FractionalPart, instead of Frac, grrr.
or worst : ImplicitRungeKuttaLobattoIIIBCoefficients
I agree to say that it is like cobol^cobol.
But the engine is fast and some pieces of code within the core are pretty neat.
I use maple with a strong canadian accent, pari-gp, mpmath and mathematica when everything else fails.
best regards,
Simon Plouffe
You might be talking about two different things. The first possibility is the aggressively prefix-oriented nature of the syntax, the pervasiveness of the pattern F[a,b,...]. Or you might be talking about "everything else". We can distinguish the two cases with the following question: does Lisp syntax also strike you as too clunky? (I am sort of annoyed that the Mathematica community does not seem to have arrived at coherent formatting rules. A bit of indentation would, in my opinion, help enormously. This is why Mathematica bothers me but Lisp doesn't.) On Thu, Aug 14, 2014 at 6:14 PM, Dan Asimov <dasimov@earthlink.net> wrote:
Is it just my imagination, or is Mathematica syntax between 5 and 100 times as clunky as it needs to be?
Sometimes I feel it's like programming with Cobol^Cobol.
--Dan _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
Mathematica is unreadable. I simply ignore Mathematica code in the math-fun posts. I'll use Sage as far as possible, and would consider buying the student version of Maple. Now, Macsyma was a complete winner. But due to a very bad decision, it is now being held hostage, and no reasonable person would pay the ransom for its release. -- Gene
________________________________ From: Dan Asimov <dasimov@earthlink.net> To: Eugene Salamin <gene_salamin@yahoo.com>; math-fun <math-fun@mailman.xmission.com> Sent: Thursday, August 14, 2014 3:14 PM Subject: Mathematica
Is it just my imagination, or is Mathematica syntax between 5 and 100 times as clunky as it needs to be?
Sometimes I feel it's like programming with Cobol^Cobol.
--Dan
I'm almost exclusively a Mathematica programmer nowadays and feel like it's the right tool for most of things I work on (recreational math, some game theory, and export of computed results to web infrastructure via JSON). I have trouble remembering the built-in function names though, and usually work with a five-page long cheat sheet right next to me that I've created myself. I often find other people's Mathematica to be almost indecipherable, though, even though I'm a frequent borrower of such material from other people's code. For example something like this subsets[list_] := Distribute[Map[{{},{#}}&,list], List, List, List, Union] gives me a headache to even look at. It's like reading one of those sentences that has four consecutive 'that' 's in it. On Thu, Aug 14, 2014 at 3:53 PM, Eugene Salamin via math-fun < math-fun@mailman.xmission.com> wrote:
Mathematica is unreadable. I simply ignore Mathematica code in the math-fun posts. I'll use Sage as far as possible, and would consider buying the student version of Maple. Now, Macsyma was a complete winner. But due to a very bad decision, it is now being held hostage, and no reasonable person would pay the ransom for its release.
-- Gene
________________________________ From: Dan Asimov <dasimov@earthlink.net> To: Eugene Salamin <gene_salamin@yahoo.com>; math-fun < math-fun@mailman.xmission.com> Sent: Thursday, August 14, 2014 3:14 PM Subject: Mathematica
Is it just my imagination, or is Mathematica syntax between 5 and 100 times as clunky as it needs to be?
Sometimes I feel it's like programming with Cobol^Cobol.
--Dan
_______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
-- Thane Plambeck tplambeck@gmail.com http://counterwave.com/
You may be interested in a 2002 Usenet post by Kent M Pitman, in which he tells part of the early history of the Mathematica syntax. http://www.ymeme.com/why-wolfram-(mathematica)-did-not-use-lisp.html Jeff On Thu, Aug 14, 2014 at 6:14 PM, Dan Asimov <dasimov@earthlink.net> wrote:
Is it just my imagination, or is Mathematica syntax between 5 and 100 times as clunky as it needs to be?
Sometimes I feel it's like programming with Cobol^Cobol.
--Dan _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
participants (7)
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Allan Wechsler -
Dan Asimov -
Eugene Salamin -
Jeff Caldwell -
Simon Plouffe -
Thane Plambeck -
Tom Rokicki