GISfilter -- I have a PostGIS table containing spatial data in the form of a few thousand shapefiles. Anybody know a quick way I can move *all* of them by about 40 metres? [more inside]
posted by genghis
on Jan 10, 2009 -
Applied Math Filter: Help me use math!
I'd like to learn more about mathematics and it's practical applications - particularly in Computer Science [more inside]
posted by dcbarker
on Aug 1, 2008 -
How can I help my 6 1/2 year old son to *get* maths? It hasn't clicked with him at all and I find myself getting frustrated with having to repeat really basic stuff when helping him with his homework. I'm not a maths genius myself and I really don't want to put him off by getting cranky because he's just not getting it. How do I help him get it? [more inside]
posted by h00py
on Jul 30, 2008 -
I am useless at mathematics. If company A grows at 5% a month, how much bigger is it after one year? [more inside]
posted by dydecker
on Jun 13, 2008 -
How can I tile a sphere using the minimum number of differently shaped units? I have a 3 meter diameter sphere and I need to tile it using units that are each about 400 square cm (ie like a 20 x 20cm square). The units must be flat (ie, not spherical triangles). [more inside]
posted by silence
on Jun 2, 2008 -
I have a question about persistence of vision and flashing lights... There will be maths and biology involved. [more inside]
posted by twine42
on Feb 6, 2008 -
Where am I going wrong with this (very simple) implicit derivative? [more inside]
posted by PuGZ
on Nov 3, 2007 -
Time for a ridiculous math question: I've got F=255M^(-1.08) and I need to work out M. [more inside]
posted by cholly
on Oct 24, 2007 -
Why is it that when I solve the inequality 0 ≤ arccos(x) <> cos(π/4)? Why do the operators switch direction?> [more inside]
posted by PuGZ
on Oct 19, 2007 -
ABC x D = BADC. What single numbers (1-9) do the letters represent?
Is there any way to arrive at the answer (a) by logical deduction all the way rather than with some trial-and-error and (b) so that a 10-year-old can follow the logic?
posted by londongeezer
on Sep 16, 2007 -
Imagine a cube-shaped building, with ten cube-shaped rooms along each side (10 rooms long, 10 high & 10 deep). Each cubular room has 4 walls, 1 ceiling and 1 floor. Each of the 6 interior
surfaces in all 1000 cubular rooms is decorated with a different piece of art.
The rooms can be moved around the building, as if it were an enormous Rubik's cube, but they can also be spun on their axes, so all 6 walls of all 1000 cubes is capable of touching all the others (if the cube is so arranged).
How many combinations of art within the 'Cube Gallery' are possible? If you can run me through the workings of the maths I would be extra grateful. Also, what technical words/phrases/language are useful/interesting in expressing this concept? [more inside]
posted by 0bvious
on Apr 24, 2007 -
ProbabilityFilter: Can I predict, from my bowling average, how many games it will be (on average) until I bowl a perfect 300 game? [more inside]
posted by roofus
on Feb 19, 2007 -
Do the curved triangular shapes made when cars (or even pedestrians) take "shortcuts" at T-junctions (seen here near my house
and here in Western Sahara
, although this seems like a deliberate one) have a name? What's the mathematics behind them? The psychology?
posted by Jimbob
on Aug 25, 2006 -
Two objects, both mass 1kg are placed 1m apart in a total vacuum. How long would it take for the force of gravity to pull them together (assuming no other forces act)? [more inside]
posted by alby
on Jan 4, 2006 -
A crystal consists of 100,000,000 layers of atoms such that there is 1 atom in the first layer, 3 in the second, 6 in the third, 10 in the fourth, 15 in the fifth, and so forth. Exactly how many atoms are there in the entire crystal? [more inside]
posted by Kwantsar
on Oct 8, 2005 -
I am trying to find some good interactive Maths tutorial software which goes from basic algebra through to Differential Equations and maybe beyond.
Can anyone recommend anything with the emphasis on the interactive side - something which can keep me interested so nothing too dry - a nice colorful multimedia approach would be ideal.
posted by empedia
on Jun 12, 2005 -
Here's a question for the mathematically minded. A lot of the work I do involves rolling materials such as paper or plastic film onto rolls. Now, while I normally can guess by sight or weigh a roll to determine how much is on it, I got to wondering... [more inside]
posted by tomble
on Apr 27, 2005 -
Mathematical imbecile question: what's the simplest, most universal way to add a list of vectors? [more inside]
posted by Jimbob
on Feb 19, 2005 -
Exam time. 2 weeks until some massive exams, which mostly consist of memorising and regurgitating code snippets and proofs for maths theorems out. Any tips/hints for last minute revision to round off longer term memorisation?
posted by Mossy
on May 26, 2004 -
How can a major key sound confident and happy, while a minor key can sound sinister or sad? Is it just centuries of musical brainwashing, or is there a real mathematical explanation?
posted by Pretty_Generic
on May 7, 2004 -
I'd like to learn Math. I'm particularly interested in learning trig and calculus. I'm don't need to learn these disciplines for any purpose. I'm just interested. I'm a reasonably bright guy, with a logical mind (I've worked as a programmer), and I'm a good self-learner. I'm not in a rush (don't mind working at this for a few years). What books/resources would you recommend? I should probably go all the way back to Algebra, which is pretty much where I left off in High School years ago.
posted by grumblebee
on Dec 27, 2003 -