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Apr
5
answered ContourPlot with parameter
Apr
3
comment Can the elements of a list always be sorted into a canonical order?
Note that DeleteDuplicates doesn't sort, so for example you get False for SubsetQ[{2, 1}, {3, 2, 1}]. You probably meant to use Union
Mar
29
answered Efficient evaluation of function defined by multiple Sum
Mar
29
comment Translating MATLAB's cell2mat into Mathematica
@rm-rf, I hesitated too, but figured that without an example it was my choice how to define the Mathematica "equivalent" of [2,3,4].
Mar
29
answered Translating MATLAB's cell2mat into Mathematica
Mar
27
awarded  Yearling
Mar
26
comment DSolve fails to solve second order PDE
In the tutorial on second-order PDE's it says "DSolve can find the general solution for a restricted type of homogeneous linear second-order PDEs..." Unfortunately this equation is not of that type (it has a non-vanishing non-principal part). So I don't think there's anything wrong as such, it's just that Mathematica can't solve this PDE.
Mar
25
comment Find root approximants for low-precision numbers
How about changing the precision of the input: RootApproximant[1.41`3]
Mar
24
comment How can I detect a rectangular region of interest in a picture?
Same here with v8 on Win7.
Mar
24
comment LinePlot in For loop
Thanks @cormullion, maybe it's a version thing. The shorthand works for me in 8.0.4
Mar
24
revised LinePlot in For loop
added 5 characters in body
Mar
24
revised Plotting a large number of data points
edited tags
Mar
24
answered Plotting a large number of data points
Mar
24
answered LinePlot in For loop
Mar
23
awarded  Nice Answer
Mar
23
comment Faster way to convert triangle list to edge list with no duplicates
You've misunderstood the question. The requirement is for a list of all the edges in the whole triangulation, without any duplicates. So if the input data was {{1,2,3}, {3,2,5}} your code gives a total of six edges {{{1,2}, {2,3}, {1,3}}, {{3,2}, {2,5}, {3,5}}}. But the edge {3,2} in the second triangle is a duplicate of the edge {2,3} in the first triangle. The desired output is a list of the five unique edges {{1,2}, {2,3}, {1,3}, {2,5}, {3,5}}
Mar
22
comment OpenCL Dot Product
@s0rce, you're welcome. The real benefit of having GPU code for this sort of ultra-simple procedure is when you already have data on the GPU. A while ago I wrote a CUDA kernel to do an element-by-element 2D complex array multiply. As a standalone function it was slower than just doing C = A B in Mathematica, but the overall calculation was an iterative process including 2D FFTs (where the GPU really shines). Having the multiply function in CUDA meant I could load the GPU memory once, do everything on the GPU and then copy the result back to the CPU.
Mar
22
answered Faster way to convert triangle list to edge list with no duplicates
Mar
21
answered OpenCL Dot Product
Mar
20
comment Why is this Mandelbrot set's implementation infeasible: takes a massive amount of time to do?
It takes a long time to calculate because you are doing exact arithmetic with very large numbers. You will want to use machine precision for computing fractals in any reasonable time. More importantly, why are you computing the sequence for an escaping point? I think you need to read more and code less until you have a basic understanding of what you're trying to do.