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21h
comment Speed up calculation
@belisarius, the pixels injected into OP's superImg increase in value as the image list is stepped through. So the final value in any pixel is always the maximum.
1d
comment Better answer to Santa's riddle about sum of a number's divisors?
@Apo, x matches a Sequence in that pattern, so Times[1, x] splices the sequence into Times, ie it gives the product of the elements in x. It's a nice trick when you're playing golf but probably best avoided in code that you might want to read again one day...
2d
comment My code does not give the same results on mathematica 9 and 10
I get the same as @Kuba - no difference between versions 9 and 10.
Dec
15
comment CUDA paclet and Mathematica 10.0.2 code problem
It's working okay for me with paclet version 10.0.0.1 on Windows 7. What C compiler are you using?
Dec
15
comment Simple image processing very slow
For finding the positions this should be quite fast: SparseArray[UnitStep[imgData - 50]]["NonzeroPositions"]
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
9
comment How to conveniently stop a programme without aborting the computation
Do you mean to pause the calculation so that it can be resumed later? Have you seen this: reference.wolfram.com/language/tutorial/…
Dec
6
comment AssociationMap loses definition. Bug?
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
21
comment Fit inside a module
As funnypony points out, you have simply missed a few semicolons at the end of lines. Voting to close as trivial mistake.