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Mar
28
answered Trying to prove that $x\sin(\frac{\pi}{x})\ge\pi \cos(\frac{\pi}{x})$ for $x\ge 1$
Mar
26
comment SIGSEGV error with 3D Plots
I use CentOS 5 and Fedora 15 & 16. With CentOS I had the same problem but only with graphics with many points. In Fedora 15 it always crash, but in Fedora 16 it doesn't. I tried with M7, M8, and M8.0.4. Updating from 8.0.1 to 8.0.4 doesn't help. Problem is not M but the system.
Mar
25
answered Replacing composite variables by a single variable
Mar
25
comment Splitting words into specific fragments
Maybe it works like the Overlaps option: StringPosition["archbishop", altelem, Overlaps -> All].
Mar
24
awarded  Quorum
Mar
23
comment How to generally match, unify and merge patterns?
@celtschk Yes, you are right, what I meant was a PatternUnion that simplifies too, simple union and intersection might be done using || (or Alternatives) or && as you showed. But like Union (which merges the list and delete duplicates) that function should simplify too. Interesting problem.
Mar
23
awarded  Civic Duty
Mar
23
answered Setting parts of a list
Mar
22
comment MapThread on a nested Map
I think the problem is not nested map, but nested pure functions with &. Try using Function as @ruebenko answer.
Mar
22
comment MapThread on a nested Map
Using Function is the best option to see if every thing is applied when you want.
Mar
18
comment Mathematica: finding min/max in list
+1. I did think about ordering, but used to think it was going to be terribly slow.
Mar
18
comment ParametricPlot3D creates a blank graphic in this case
Very clever use a transformation of variables. But anyway I think the question was why the plot fails. But this is one of the best workarounds.
Mar
16
comment Organizing similar datasets using DownValues instead of Contexts
This reminds me "dict" in python. Good way to get all the keys quickly.
Mar
16
comment How to prevent the welcome screen from showing up after I close my last notebook? (Ubuntu 11.10, MMA 8.0.4.0)
@MichaelWijaya yes, maybe I didn't explain myself well, what I wanted to point out is that the same keys can close both windows, so hitting Ctrl W twice will quit (but if you are already using the keyboard you should use Ctrl Q).
Mar
16
comment How to prevent the welcome screen from showing up after I close my last notebook? (Ubuntu 11.10, MMA 8.0.4.0)
I miss the new empty notebook :P. I usually use keyboard so I use Ctrl W for closing notebooks, and Ctrl Q to close all session notebooks. Ctrl W closes the welcome screen too.
Mar
16
comment Sort per column
Yes, it does! I was thinking about adding the priority as the number of columns instead of using a number to define ordering but that does the same trick.
Mar
16
comment Sort per column
I don't know how efficient it is, but I don't see any problem. What I like is that it would be very easy to add a new parameter to change not only the direction of each sorting but the priority of columns (in your function it would mean building the w considering it).
Mar
15
comment Creating a table/Matrix during a For loop
@Mr.Wizard your last comment points out what István started saying: there are a million ways to do this!
Mar
15
comment Sort per column
@Mr.Wizard yes, it works only on numeric data, but I think it is the easiest way to be remember. Your generalization is very nice, but needs to be added to your personal package of utilities (something worth having).
Mar
15
comment How can the {x,y,z} points that fall on the outer boundary of a set of values be selected and smoothly surfaced?
With Graphics3D[GraphicsComplex[data3D, Polygon[surface[[2]]]]] I can run it too. TetGenConvexHull returns me to vectors, the points and the surface polygons.