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Nov
19
comment Upvalues and order of interpretation
@Kuba, I think this is more a question of evaluation control than pattern specificity. In QUAD["k1"]->2 OP needs QUAD["k1"] to partially evaluate to give an elementDefinition expression, but then for the elementDefinition SubValues not to evaluate - so that the UpValue definition kicks in instead when Rule evaluates. I'm not sure how this can be done. Personally I would steer clear of using built-ins like Rule as part of a homebrew syntax.
Nov
19
comment How do you apply an algorithm individually to an array with many graphs
Regarding your "obviously it doesn't like doing that" snippet: the outermost iterator should be given first. Like this: Table[stuff, {j, allgraphs}, {k, Max[VertexDegree[j]]}]
Nov
19
comment Maxwell propagator problem 2D
You probably want {ez, hy, hx} outside the Do loop so that it is returned from the module. Also I suggest you get the basic algorithm working before trying to compile it. And be aware of the difference between Dot and Times.
Nov
18
comment How to do algebra on summations of variable expressions?
@Mr.Wizard, I wonder if some of these Sum transformations are already built in, somewhere inside the colossal rule set for Simplify. But I agree wholeheartedly with your comment.
Nov
18
comment Comparison of Dispatch objects ureliable in Mathematica 10
@Szabolcs, in general rule order does matter though. Or is it different for Dispatch?
Nov
16
comment How to programmatically extract mathematical formulas from Word with Mathematica 9?
It looks like the WordprocessingDocument is this from the Open XML SDK. I had a quick look at it too, but I'm not at all familiar with .NET and it seemed too much like hard work for a Sunday distraction :-)
Nov
15
comment How can I Integrate large trigonometric expressions more efficiently?
No, please don't delete your original. I think it's good to keep it as it shows how you would approach similar problems in cases where the integrals aren't trivial.
Nov
15
comment How can I Integrate large trigonometric expressions more efficiently?
+1 Same approach I took, though since n is an integer I didn't bother with Integrate at all. Just Expand[2 Pi expr]/.{(Cos|Sin)[_]^2 -> 1/2, (Cos|Sin)[_] -> 0}
Nov
15
comment How can I Integrate large trigonometric expressions more efficiently?
What we need is an example of the original Integrate expression, not the result. And please add additional information to the question, not as comments. There is an "edit" button under the question for that purpose.
Nov
15
comment How to programmatically extract mathematical formulas from Word with Mathematica 9?
This answer includes some C# code for converting OMML to MathML. It might be some help.
Nov
15
comment How can I Integrate large trigonometric expressions more efficiently?
You need to supply a couple of examples of the integrations, otherwise we don't know why it's so slow.
Nov
11
comment Distribution of block maxima of gaussian random variables
You need to use ExtremeValueDistribution for maxima, GumbelDistribution is for minima. This is explained in the documentation for GumbelDistribution
Nov
11
comment Glitch in Filling?
Bug report now sent
Nov
10
comment Opacity function applied to Graphics Objects
Looks right to me.
Nov
10
comment Opacity function applied to Graphics Objects
I think Texture is the way to go, but for an opacity gradient the gaussian should be in the alpha channel.
Nov
9
comment Hermite method in Mathematica
A misunderstanding here, I think. The Hermite method is what the InterpolatingFunction is using (see here), not the method used by NDSolve.
Nov
9
comment Opacity renders lines incorrect in certain viewing angles
Looks like an issue with hardware rendering then, I suggest you submit a bug report to Wolfram.
Nov
9
comment Opacity renders lines incorrect in certain viewing angles
I suspect a problem with the hardware rendering engine. Does this help? Style[%, "RenderingOptions" -> {"Graphics3DRenderingEngine" -> "BSPTree"}]
Nov
8
comment TrigExpand Idiosyncracies
I assume that somewhere inside TrigExpand the pattern Sin[_]^2 f_[_] leads to different transformation rules according to whether f is a trig function or not. You have simply found a case where one of those transformations gives a result which a human mathematician would discard as inelegant.
Nov
7
comment Matrix multiplication
Yes I figured the question was more about the memory usage than the specific example, that's why I posted a comment instead of an answer. All I can really say about the speed is that I know that Dot is super-optimised for packed arrays, far far quicker than the equivalent number of arithmetic operations. I expect @ybeltukov or @Szabolcs could give a more knowledgeable explanation.