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38m
comment Buying a new computer (specifically for Mathematica)
This is an interesting Q given the lack of benchmarks. I'm also intersted in the Mac Pro but can only justify it if it's going to substantially improve execution time and can do ParallelCombine etc across multi-cores.
1h
comment Getting all physical units with prefixes
@Rojo, A New Kind of Unit.
9h
comment Alternate parameterization of a line
@bills, "Is there a nice way to make it only do the solution once?" - have you tried memoization: f[..] := g[..] = h[..]?
9h
comment How to add a column to a table that counts the number of times the lines appear?
Tally[a] // Map[Flatten]
1d
comment A more suggestive name for a useful utility Query?
@YvesKlett, btw, it also works w/ only@Thread[{"VisitStartTime", "VisitEndTime"} -> TimeObject]. Do you think double-parenthesis instead of only eg, {{key->value..}}` would work?
1d
comment Animate skips frames and hard to control speed.
Good points, but during exploratory analysis you cannot afford that cold start - too slow. Wish there were an interface to map b/w the methods.
1d
comment Getting all physical units with prefixes
Amazing. And what planet are some of these from, FluctuationStrengthUnit, HanksWool, ... PleasureUnit?
1d
comment Animate skips frames and hard to control speed.
Something to keep in mind though is a comparison b/w Mathematica & C++ - to model benzene electronic structure I think - revealed a neck to neck, something like 5 hrs vs 5 1/2 hours - so not necessarily worth compiling. The future --> VM optimization.
1d
comment Animate skips frames and hard to control speed.
Thanks for working out all those improvements that I hadn't even considered, the metric was to minimize code size. These are worth pursuing for a larger version.
1d
comment Animate skips frames and hard to control speed.
@halirutan, Im hesitant to accept below b/c I tried DisplayAllSteps->True' with AnimationRate->10` skips steps w/o actually speeding up the animation.
1d
comment Animate skips frames and hard to control speed.
Nice. However, using AnimationRate -> 10 skips steps while not actually speeding it up at all.
1d
comment Difference between Association and Dispatch
... or would have to rebuild on Erlang.
1d
comment Difference between Association and Dispatch
@LeonidShifrin, on this subject, the FTC is planning for microsec resolution for Nasdaq ("Tape C") transaction stream. In a few large hospitals there are ~10k RTLS+RFID tags on which real time monitoring is desired - coupled w/ ParallelCombine and GroupBy tasks - can Association and Dispatch scale up to these real time analytics challenges (think visulization like Tableau).
1d
comment How do I seamlessly migrate from the older Units package to Mathematica 9's Quantity objects?
Yes, glad you mention the over the network units - which are slow even w/ no firewall. Ideally would like a list of both types.
1d
comment How do I seamlessly migrate from the older Units package to Mathematica 9's Quantity objects?
I meant the new versions. Can you use the same approach to list the new built in units. I don't know of a way to extract them with, say, Names[Quantity[_, _]] --> Quantity::unknunit : Unable to interpret unit specification". What's your approach?
1d
comment How do I seamlessly migrate from the older Units package to Mathematica 9's Quantity objects?
+1 goes w/o saying. This is great stuff. Can you share the code to extract all units? WRI will surely add more (new) units, so how to catalogue them dynamically?
1d
comment How to find the period of an arbitrary mathematical function?
@DanielLichtblau, are you aware of methods to partition a finite Integer sequence into its pre-period and its period (either of which could be empty?). Eg, trajectory of 5 in the 3x+1 problem would give pre-period {5,16,8} and period {4,2,1}
2d
comment ListPicker with conditional selection
Can you Map ListPicker to columns within rows?
2d
asked Animate skips frames and hard to control speed.
2d
comment A more suggestive name for a useful utility Query?
I expected that crowdsourcing and votes might help identify a more descriptive name for this operation.