# amr

 Apr 6 awarded Yearling Apr 6 awarded Yearling Dec 5 comment How does "curved space" explain gravitational attraction?The best illustration I've seen of the equivalence principle and the basic curvature intuition of GR is in "The Mechanical Universe": youtu.be/w0SeFfV6J3k?t=13m Oct 30 asked Prevent auto parentheses matching in Xcode Sep 16 accepted List of all Visual Studio compiler errors and warnings, with their numbers Sep 16 comment List of all Visual Studio compiler errors and warnings, with their numbersThank you. In keeping with my oath I actually did write a script and was almost done (just needed to fix some edge cases) but I lost it. Whoops. Aug 30 comment Prove that G is a groupI find the reasoning is easier to follow if you draw out the table of a small group G (say 4 or 5 elements). For one, every element x must "shift" the elements differently, because otherwise you will have a row/column in G's operation table with a duplicate element, and that wouldn't be the table of a group. Aug 30 comment IndexError: tuple index out of range ----- PythonI was getting this message because I was passing an array to a function that was expecting a variadic sequence of arguments (eg `'{}{}'.format([1,2])` vs `'{}{}'.format(*[1,2])` Aug 5 awarded Yearling Jul 28 answered Type "myViewController" does not conform to protocol UIPIckerDataSource in Swift Jul 20 comment Functions as objectsyou might try replacing the output statements with Print[...]. i think the top-level behavior of newline-separated statements (as input into a notebook) is different when they're in a "formal" expression. Jul 16 answered how to concatenate a list of a list of strings Jul 15 comment How to create a thick spiral then extract the coordinates from the image?Regarding the spacing/interval update in your question, it's not clear to me what the simplest approach to that is, and there's a couple mathematical issues (eg the spirals are close together at the center). Maybe figuring out how to make alternating black/white spirals that are exactly touching would be a good heuristic. The quickest way might actually be to ask on the Math.SE site. Jul 15 comment How to create a thick spiral then extract the coordinates from the image?@Solarmew See my edit for one solution to that. Jul 15 revised How to create a thick spiral then extract the coordinates from the image?added 1117 characters in body Jul 14 comment How to create a thick spiral then extract the coordinates from the image?I'm currently busy but I'll see if I can figure something out later today. In any case, feel free to re-accept to someone else's answer. Jul 7 comment Image smoothing with own smoothing functioncould you not use `ImageFilter` ? also `ParallelTable` would be a quick way to parallelize. Jul 4 comment Matrix multiplication for higher dimensional matricesto clarify here, `MatrixForm` is a display function. it's used to show your results as a matrix, but is not used during calculations. you don't need to tell Mathematica "hey this is a matrix" because any rectangular list of lists is as good a matrix as you need. for example `Det[{{a, 1}, {Graphics[Disk[]], d}}]` will give an answer. this is a deliberate design feature. in particular, it means that all the functions you use for dealing with lists (such as `Reverse`) can also be used directly on matrices... and vice versa. Jul 3 comment Graphics3D artifact in Mathematica 10.1 64bit Home Edition - Windows 7?could it be some kind of post-evaluation function that has attached itself to Graphics3D outputs that puts them in `Pane`? i don't remember what the commands are but the setting might be somewhere in `AbsoluteOptions[EvaluationNotebook[]]`. Actually, if this is the case it should be visible if you `// FullForm` the graphics3D output. Jul 3 comment How to create a thick spiral then extract the coordinates from the image?Just as an addendum, `ImageCrop[image]` is useful for cutting back exactly after over-padding (such as with PlotRangePadding in this case).