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Jul
9
comment How to find all data points within closed curve
for getting the points out of the plot, I think Leonid method might be more portable than depending on [[1,1,3,2,1]] indexing as this might change in future versions. As in points = Reap[ParametricPlot[{Sin[u], Sin[2 u]}, {u, 0, 2 Pi}, EvaluationMonitor :> Sow[{Sin[u], Sin[2 u]}]]][[2, 1]]; stackoverflow.com/questions/5364088/…
Jul
8
comment Implicitly differentiate an equation, then solve the resulting equation
what is z? constant? function of x?
Jul
7
comment Im trying to model balls in a box with NDsolve, but the balls keep escaping the box
What I would do is integrating for a small time step, then do the detection of collision outside NDsolve not inside using events, then call NDSolve again for a small time step, and so on. see this demo demonstrations.wolfram.com/…
Jul
7
comment how to make contents of package visible to the autocomplete system?
It should work on OSX then, please report to wolfram@support.com (assuming you restarted everything clean, and rest everything etc.. and it still does not work)
Jul
7
comment how to make contents of package visible to the autocomplete system?
it also works on windows 7, V 9.01 screen shot !Mathematica graphics
Jul
7
comment Switch inside Manipulate controls statement
@m_goldberg But I qualified it by saying "at least I never seen it before." :) I was lazy to actually try it. But I learned something new today about Manipulate.
Jul
7
comment Switch inside Manipulate controls statement
You can't do this. You can't put controls inside Switch, at least I never seen it before. But if you post full code, it will help try it out than spend time to try to recreate it.
Jul
6
comment How to use multiple pure functions correctly?
Just to reinforce the point in the answer below. This shows the two # do not clash when using Function as in data = {1, 2, 3, 4, 5}; intervals = {{0, 1}, {1, 4}, {3, 4}}; Map[Select[data, #] &, (Function[i, IntervalMemberQ[Interval[#], i]] & /@ intervals)] The second # is bounded to the Function and the outer # does not see it.
Jul
6
comment Plotting a multivariable function
Ok, you can try Plot3D[m[x, y], {x, 0, 5}, {y, 0, 5}, PlotRange -> All] and see if this works
Jul
6
comment Plotting a multivariable function
You can't just write Plot3D[m,...] you have to actually call m with the arguments. Try m[x,y]
Jul
5
comment Decimal output from a simple equation
with little less typing "x =0.0000000000000000036`1";
Jul
4
comment ToExpression fails with long nested string expressions
fyi, tried it on V10 at WPC, and it failed there at 351 not 182. Not sure if this makes any difference. !Mathematica graphics
Jul
4
comment How to apply function on list of lists with different sizes
Thanks. May be it was easy, but I just did not see it :) Yes, this does what I want. But feel free to close it if you feel it will not be useful for future visitors. (I overlooked the {2} trick at the end)
Jul
4
comment Evaluating an If expression inside Dynamic
@eldo, you are right. Will correct, thanks.
Jul
4
comment Problems with Solve
@m_goldberg that is what I did first. Broke that clooped up code into separate cells to see if each work. The problem is Solve can't solve the equations even with Real option. I do not know why people do not break code into separate pieces and run each in sequence any more like we used to do in the good old days. Wrapping functions inside other functions might make things look cool, but it makes debugging very hard.
Jul
4
comment Problems with Solve
Solve::nsmet : "This system cannot be solved with the methods available to Solve." You can't expect magic to happen, if when using Mathematica. Some equations can't be analytically solved.
Jul
4
comment Why are functions called first-class objects in Mathematica?
The f = 9; f[x_]:=x^2 error since now the second line reads as 9[x_]:=x^2
Jul
4
comment Geometric Transformation not working - degenerate points?
This error message is not documented anywhere in the help. So only suggestion is to contact support@wolfram.com, someone with access to the source code internally will be able to know. It could be simply that it does not support larger than 3 dimensions space.
Jul
3
comment Parallel kernel and front end
from help, it says: generates a monitor cell that shows the continually updated current value...In a notebook, the monitor cell normally appears directly after the cell in which Monitor[expr,mon] is evaluated so clearly Monitor requires a frontend. Can't be used in script/batch.
Jul
2
comment Graphics elements in a 2D lattice
maybe mathematica.stackexchange.com/questions/8841/… or calculuslab.deltacollege.edu/ODE/7-1/7-1-0-c-mma.html also this is useful stackoverflow.com/questions/8905726/…