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Apr
7
comment StreamPlot,smooth curves
WOW ! - an interesting use of the powerful fundamentals of Mathematica!
Mar
14
comment Speeding up inversion of symbolic matrices by invoking caching
@DanielLichtblau thanks for pointing out that Simplify benefits from caching (and not Inverse) - something new. I was thinking something along the lines of DumpsterDoofus's answer, which executes faster than the Inverse (I think I need to re-time it removing the Simpllify around the Inverse)
Mar
13
comment Speeding up inversion of symbolic matrices by invoking caching
Sorry. My question was, is there any predicatable takeaway from the caching - i.e. something that I can count on (in terms of time-saving)? Is there anything I can do as a user to speedup further operations. The doubt here is since I am not aware of how the exactly caching helps - does it extend to only the EXACT SAME matrix (wherein memoization would solve it) OR does the caching speedup inversions of the SAME ORDER (i.e. for ANY other matrix of 12x12) OR would it speedup ANY ORDER less than the current order OR anything else ?
Mar
13
comment Problem inserting data into a mysql table with column names having a space
Again problematic. I tried to create the table manually ,outside Mathematica, since I got some error when I was trying to set the default value of the string to be ''. But even after that addressing columns with a space in the name throws error. @Hans - how do I find what mode the JDBC is mimicking. I am wondering if its a problem with MMA and the Uniserver (I am able to access these columns from PhP on the same machine though)
Mar
13
comment Difference between AbsoluteTiming and Timing
@J.M. - something interesting - i noticed Timing[100000!;] is shown with "Second" in the output, whereas I dont see that on my machine's output
Mar
12
comment Problem inserting data into a mysql table with column names having a space
"\"Col 1\"" works for creating column - but is problematic while inserting using SQLInsert. Tried [Col 1] - it does not help either
Feb
25
comment Behaviour of Simplify when used with ArcTan and ComplexExpand along with assumptions
Solved . . . . .
Feb
22
comment Behaviour of Simplify when used with ArcTan and ComplexExpand along with assumptions
@SimonWoods - Can you add it as an answer so that I can Accept it
Feb
22
comment Behaviour of Simplify when used with ArcTan and ComplexExpand along with assumptions
Thanks you were right. On removing the assumption L>0 from the Simplify[] and the results match!
Feb
5
comment Plotting ContourLabels on ContourPlot3D
Thank you for the solution
Feb
4
comment Plotting ContourLabels on ContourPlot3D
I would like to add the contours for the mesh (black) lines here
Feb
4
comment Plotting ContourLabels on ContourPlot3D
@Artes : Thanks for pointing it out - the solution was to overlay the different plots. Whereas in this case of plotting contourLabels, one cannot user overlay (at least directly), since the position of the contourlines are not known apriori. Maybe one can get the contours from the expression (mathematica.stackexchange.com/questions/20281/…) and then evaluate the value of the function there and put a value there. But I was interested in knowing if there is a way to get it done using contourLabels
Oct
30
comment Bound on number of function evalulations in FindMinimum
to make sure it performs utmost iters no of evals, need to replace >= with = (can't edit it - min num of chars required for edits to be accepted)
Oct
30
comment Bound on number of function evalulations in FindMinimum
+1 for fval = fun[x]. It works
Oct
29
comment Shaving the last 50 ms off NMinimize
@OleksandrR. Is there an equivalent for FindMinimum. I tried Trace[FindMinimum[x Cos[x], {x, 2}], TraceInternal -> True] and I see something like OptimizationInternalModifiedCholesky$4575`.
Oct
27
comment Reference request for neural network programming in Mathematica
Is the NeuralNetworks package still under development? The example here (library.wolfram.com/examples/exchangerate) and the official documentation (media.wolfram.com/documents/NeuralNetworksDocumentation.pdf) seem to use <<LinearAlgebra`MatrixManipulation` which is obsolete!
Oct
9
comment Extract date from a not well-formed string
Nice find! Thanks
Oct
3
comment ParallelMap and Sow/Reap - not behaving as expected?
But how is this behavior of Reap@Map@Sow giving {} explainable?
Oct
3
comment ParallelMap and Sow/Reap - not behaving as expected?
Thanks for sueggesting ParallelCombine. An interesting find!
Sep
25
comment Raise systemwide keypress event
Thanks for the solution. I was using Autoit and it is a Windows-specific solution. Doing it using Mathematica would be cross-platform I thought