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Dec
13
comment about the design of Part related to Association
With your last question you are misunderstanding the effect of Span. It returns the selected parts wrapped in their original head. So you only get a List back if you are extracting parts from a List. For example f[1, 2, 3][[1;;2]] gives f[1, 2] not {1, 2}.
Dec
13
comment about the design of Part related to Association
@matheorem, it looks like there is still some work to do with pattern matching on Associations, but I wouldn't expect the behaviour with Part to change.
Dec
13
comment about the design of Part related to Association
@matheorem, there's some discussion of that here. I don't claim to fully understand the situation, but I have found that associations mostly make sense if you regard the values as being what's really there at level 1, and the keys as ephemeral magic labels which are transparent to most operations and which vanish as soon as the value is no longer contained inside an association.
Dec
13
comment about the design of Part related to Association
@matheorem, because the value is not the rule "a"->1, it is just 1. Note that FreeQ[<|"a"->1|>, Rule] is True - there is no Rule in that expression, despite appearances.
Dec
13
comment ListContourPlot interpolation fails if x and y axes have different scales
It used to be possible to use Method -> {"DelaunayDomainScaling" -> True} in the contour plot to work around this issue. Unfortunately it doesn't seem to work in version 10.
Dec
13
comment about the design of Part related to Association
I agree, the behaviour of Part with Association is consistent and expected.
Dec
12
comment Piecewise smooth rectangle pulse
Hyperbolic tangents are useful for smooth step functions, e.g. Plot[0.5 (Tanh[10 (x - 1)] - Tanh[10 (x - 3)]), {x, 0, 4}]
Dec
6
comment AssociationMap loses definition
I cannot reproduce this in v10.0.1 on Windows 7 (64-bit). Have you tried reinstalling Mathematica?
Dec
5
comment How to exclude the diagonal in a MatrixPlot?
@becko, it would help if you supplied an example matrix to demonstrate the problem
Nov
25
comment How do I draw a pair of buttocks?
@Ludwik, dammit I knew I should have paid attention in anatomy class!
Nov
25
comment How do I draw a pair of buttocks?
@Öskå, I agree, your butt is nicer than mine.
Nov
22
comment Regarding Evaluated True
This appears to be a bug. At some point during the plot creation (inside System`ProtoPlotDump`iPlot) the Filling option value is processed to generate a full filling description for each plotted curve. This process does not take into account the Evaluated option and so sees only a single expression in your second example, and therefore only creates a Filling specification for one curve. I suggest you submit a bug report to Wolfram.
Nov
22
comment Obtain polygons describing all intersections of many polygons
polygons[[9]] includes each perimeter point twice, so it is all hole.
Nov
20
comment Minesweeper beta:How to Dynamic a lot of graphics with high-speed
Or ToExpression["a=" <> ToString[3]]
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
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.