1,412 reputation
416
bio website linkedin.com/pub/eric-brown/…
location Evanston, Illinois
age
visits member for 1 years, 6 months
seen Apr 19 at 22:34

Jul
4
accepted Giving JLink Huge Memory by Default
Jul
3
asked Giving JLink Huge Memory by Default
Jul
3
comment Importing specific columns of a .txt file
(I am not sure why this is getting dinged.) I don't know how to do this either with ReadList. Anyway, it may be just as easy to read the whole data set with ReadList, then take the columns with dataReadIn[[All,{1,4}]] Otherwise it could be a job for OpenRead, Read, Skip, etc.
Jul
2
comment Doubts on scripting: error messages when trying to run and how to process lots of files
@rm-rf He only has hundreds, so I guess he should do it in the front end ;-)
Jul
2
comment Doubts on scripting: error messages when trying to run and how to process lots of files
Yves and rm: He clearly states that he wants it scriptable. The front end may not be appropriate for his tasks.
Jul
1
comment triple NIntegrate fails
Another suggestion: if you need the 10^-48 stuff for scaling, then you may want to move that inside of the NIntegrate so that it does not blow up or even vanish.
Jul
1
comment triple NIntegrate fails
Another issue: 1) I would combine all the NIntegrates into one 2) Is it possible for the argument to the Sqrt to become negative? Plot3D[r12^2 + r13^2 - 2 r12 r13 n /. n -> 10, {r13, 0, 150}, {r12, 0, 150}]
Jul
1
comment triple NIntegrate fails
Some suggestions: 1) please don't use capital C because it is already used in Mathematica. Maybe try small c. 2) T is not defined in your equation, neither as a parameter nor as a variable for integration.
Jul
1
comment Complex valued 2+1D PDE Schroedinger equation, numerical method for `NDSolve`?
@Stefan +1 Are the AccuracyGoal/PrecisionGoal needed?
Jun
30
comment Speeding up TIF import
(I suspect that you want a purely Mathematica function but) Have you tried to import with libtiff via MathLink? If you do a lot of reading, maybe it's worth investigating it.
Jun
30
revised How do I test for the occurrence of an error message and act on it?
added some comments to the code to make it more understandable
Jun
30
answered How do I test for the occurrence of an error message and act on it?
Jun
30
comment WeatherData for the 15th day of each month
I interpret it to mean the "Month" of {2007,1,15} would be "MedianTemperature" in Jan. 2007. The next month's date is {2007,2,1} and that would be Feb. 2007.
Jun
30
comment WeatherData for the 15th day of each month
It seems DatePlus simply increments the month field of {y,m,d} -- I guess this is the behavior you were hoping for. "gives measurements aggregated over the time period represented by step" would seem to mean only month matters, and the behavior seems consistent with the documentation. (But not consistent with DatePlus, I agree)
Jun
30
comment WeatherData for the 15th day of each month
1) If you are stepping by Month, then one might have to assume that the "first" of the month is the stepping stone. i.e. 1 Month is not necessarily 30 days. 2) It seems your @/ idiom is calling WeatherData many times, not just supplying a list of dates, which is related to 3) not returning a value with one date supplied seems like a bug, or perhaps unclear documentation for WeatherData.
Jun
26
comment Function or script which maxes out the CPUs?
@lynvie my pleasure. Sounds reasonable, it's possible that it is cores instead of hyperthreading, but it is also possible that a) your license restricts you to 4 cores and/or b) you have the number of cores manually hard-wired in your Parallel Preferences.
Jun
26
comment Function or script which maxes out the CPUs?
@OleksandrR. I have an 11 inch macbook air, which is 2 GHz, dual core. (Model MacbookAir5,1)
Jun
26
comment Function or script which maxes out the CPUs?
@OleksandrR. Interesting you say that: on my Macbook Air (i7) the matrix multiply only uses two cores ("processors") whereas the Parallel operations, shown in my answer, get four (hyper threading?)
Jun
26
answered Function or script which maxes out the CPUs?
Jun
26
comment Function or script which maxes out the CPUs?
…but something tells me you are looking for saturation with a function that is called via the "Parallel" statement.