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Jan
8
comment Extracting parts of a list subject to a condition
The question is not completely clear (for a start you have triplets {x,y,z} where y is actually x...) Are you just looking for the triplet with the most negative value of z?
Jan
7
comment After definite integration the result is still integration variable dependent!
10.0.2 gives the same result as 10.0.1
Jan
7
comment Solve a system of equations with double subscripts
You will get a better response if you include code which people can copy and paste into Mathematica.
Jan
5
comment Calculating sum
The most obvious issue with your code is that you are assigning values to mm1 and mm2 and then trying to use them symbolically. Why not use different symbols in the definition of xxm?
Jan
3
comment What is the most convenient way to read definitions of in-memory symbols when we don't have the source files? (Spelunking tools)
@VladimirReshetnikov, thanks for the notification. There are a few similar examples though I never got around to debugging it. If you come up with a workaround please let me know.
Dec
30
comment How to prevent simplification?
I'm sure this is a duplicate but I can't find the previous question.
Dec
30
comment Pattern Matching in Lists
This should be fairly easy, but anyone wanting to help you is first faced with the boring task of generating a suitable dataset to test with. If you include an example dataset in the question (say a dozen rows or so) you will be much more likely to get an answer.
Dec
28
comment RegionPlot of an area inside a polar plot (or its equivalent parametric plot)
I think ImplicitRegion[{2 Pi < Sqrt[x^2 + y^2] - ArcTan[x, y] < 4 Pi, x > 0, y > 0}, {x, y}] should give the region you want, but it doesn't seem to work.
Dec
26
comment How to assemble and disassemble a function into steps
I tried to implement a part of this some time ago, a button which would break apart a CompoundExpression into separate input cells and another to reverse the process. I seem to have lost the notebook though. I do recall that I was never really happy with it and decided that it was easier just to use the divide and merge cells keyboard shortcuts.
Dec
18
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.
Dec
17
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...
Dec
17
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.