wolfram-mathematica

I have modified my notebook's stylesheet to include a StyleData["Todo"] that inherits from StyleData["Item"] . It changes the cell dingbat to a checkbox. In the stylesheet editor: Cell[StyleData["ToDo", StyleDefinitions -> StyleData["Item"]], CellDingbat->DynamicModuleBox[{$CellContext`color$$}, CheckboxBox[ Dynamic[$CellContext`color$$], {RGBColor[1, 0.5, 0],RGBColor[0,Rational[2, 3], 0]}, Background -> Dynamic[$CellContext`color$$]], DynamicModuleValues :> {} ], ] The problem is that the state of the checkbox, when used in a notebook, is not saved between Mathematica sessions. I thought the

By default Mathematica throws a warning message if I use the same name for both Blank and BlankSequence patterns: f[{x_, ___} | x__] := g[x] Pattern::patv: Name x used for both fixed and variable length patterns. >> Pattern::patv: Name x used for both fixed and variable length patterns. >> Yet the function works as I desire: f[{1, 2, 3}] f[1, 2, 3] g[1] g[1, 2, 3] Therefore, is it safe to use Off[Pattern::patv] and continue as I please? I am aware of a variety of different, more verbose methods that can accomplish the same task, and it is not my desire to analyze their respective merits. I am

After playing with Mathematica's symbolic and numerical capabilities, I find it to be a decent programming language, too. However, something making it less appealing as a general-purpose language is the lack of C-like struct data type (or the record type as known in Pascal). How can I get around this problem? sakra Update : Mathematica 10 has introduced Association , which has many of the most important properties of a struct . (See new answer .) The original, somewhat deprecated version of this answer is below. You can use a Mathematica rule lists to mimic a C-like struct data type. E.g.,:

What is the best way to find the period in a repeating list? For example: a = {4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1, 2} has repeat {4, 5, 1, 2, 3} with the remainder {4, 5, 1, 2} matching, but being incomplete. The algorithm should be fast enough to handle longer cases, like so: b = RandomInteger[10000, {100}]; a = Join[b, b, b, b, Take[b, 27]] The algorithm should return $Failed if there is no repeating pattern like above. Szabolcs Please see the comments interspersed with the code on how it works. (* True if a has period p *) testPeriod[p_, a_] := Drop[a, p] === Drop[a, -p] (* are all the

I have never used python but Mathematica can't handle the equation I am trying to solve. I am trying to solve for the variable "a" of the following equations where s, c, mu, and delta t are known parameters. I tried doing NSolve, Solve, etc in Mathematica but it has been running for an hour with no luck. Since I am not familiar with Python, is there a way I can use Python to solve this equation for a? You're not going to find an analytic solution to these equations because they're transcendental, containing a both inside and outside of a trigonometric function. I think the trouble you're