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Jan
3
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Dec
25
awarded  Popular Question
Dec
18
comment How to constrain memory usage on HPC?
Sorry for late response. I tried Evaluation -> Parallel Kernel Configuration, uncheck the "try to relaunch failure kernels". But it didn't work.
Dec
14
comment How to constrain memory usage on HPC?
I currently use Linux and Mathematica 8. I don't know how to use lowlevel link-communication to do this. But I found that even if you don't evaluate ParallelTable expression. Just a normal non-parallel expression like RandomInteger[100, {500, 500, 500}] for second time, the memory will still not get controlled.
Dec
14
comment How to constrain memory usage on HPC?
Thank you halirutan! I tried your code. But it seems that it doesn't work. Try ParallelTable[tt[i] = RandomInteger[100, {500, 500, 500}], {i, 1, 2}], you will see that the kernels are closed at first, then relaunched automatically and evaluate well give the result regardless of the memory
Dec
13
revised How to constrain memory usage on HPC?
added 16 characters in body
Dec
12
revised how to deal with so many digits in plot ticks
added 213 characters in body
Dec
12
comment how to deal with so many digits in plot ticks
this is a possible way, thank you for your suggestion
Dec
12
comment how to deal with so many digits in plot ticks
@Kuba @SjoerdC.deVries Thank you for your information! I learned to style ticks. A custom tickformat is useful.
Dec
12
asked how to deal with so many digits in plot ticks
Dec
11
awarded  Nice Question
Dec
11
comment Interactively extract points from a plot (ListPlot or SmoothDensityHistogram)
Hi, Heike, Could you please tell me how to change Locator size in manipulate?
Dec
11
comment how to interactively select points inside certain region in a plot
@xslittlegrass WoW, I like your method to choose region using drawing tool, it's much more flexible to use linesegment or freehandline than polygon. And so smart to extract lines and pts from the plot. Why didn't you post an answer to that question?
Dec
11
comment Interactively extract points from a plot (ListPlot or SmoothDensityHistogram)
@SparsePine and an "undo" button is also useful, Button["undo", poly = Drop[poly, -1]]
Dec
10
comment efficient way to give nearest neighbour and next nearest neighbour of every point in a point set
Sorry, I found bugs. See this ps list here pastebin.com/GXtnVxYi This ps list contains Sqrt, and if you try ps=N@ps and add small offset to d respectively, you will find their result is different. And I can confirm, add offset gives right result, because the right result will compatible with my other code. But merely add small offset without ps=N@ps will effect the performance much. So I conclude that ps=N@ps and a small offset, None is dispensable for correct and efficient code. I hope you could check this to see if my statement is right. Thank you
Dec
10
comment efficient way to give nearest neighbour and next nearest neighbour of every point in a point set
I mean if the coordinates of points contain Sqrt, then to make the code most general and correct, either to add ps=N@ps, or add a little offset to d in your code. And in terms of the identity of your code and mine, I'm not claim any precedence here, because anyway you enlightened me to use NearestFunction first. But I read through your code and test it, so I am sure we had the same idea. And finally, if I had know that you would post an answer, I wouldn't spend a whole afternoon to design a code myself :). especially when yours is more general and efficient than mine. Thank you so much!
Dec
10
comment efficient way to give nearest neighbour and next nearest neighbour of every point in a point set
Ok, are you considering to improve your answer with N? Though my method is identical to yours, but I make the label a little complex, so I'll accept yours, if there is no better method
Dec
10
revised efficient way to give nearest neighbour and next nearest neighbour of every point in a point set
added 172 characters in body
Dec
10
comment efficient way to give nearest neighbour and next nearest neighbour of every point in a point set
Well, you can try this ps={{0, 0}, {Sqrt[2], 0}, {0, Sqrt[2]}, {Sqrt[2], Sqrt[2]}}. Very odd,.but it's true, offset is necessary.
Dec
10
comment efficient way to give nearest neighbour and next nearest neighbour of every point in a point set
Thank you for your answer! I am testing now, and I also found the EuclideanDistance problem, so I use N and add small offset 0.0000001 to it, I found this small offset is necessary, see my answer.