Skip to main content

manipulate - Strange evaluating indication of output cells


enter image description here


Something like this happened when I was working with two Manipulate cells. I saved the notebook, duplicated it and only keep these two cells, and opened the notebook with a fresh kernel, it still happened immediately (in trusted directory, if not, this happens after clicking enable dynamics).


I have repeated this on Mathematica 10.1 on OS X 10.10.3 and Windows 8.1 (I am not able to open it in version 9).


So is it a bug, or an expected behaviour I am unaware of?


The code in the notebook is here:


First Cell:



Manipulate[
circle = ParametricPlot3D[{Sin[x], Cos[x], 0}, {x, -Pi, Pi}, 
PerformanceGoal -> "Quality"];
circle1 = First[circle];
circlebase = Scale[circle1, {1, 1, 1}, {0, 0, 0}];
fin = Table[
Translate[Rotate[{Point[{-1, 0, 0}]}, - i 4 Pi/1000, {0, 0, 1}], 
 2 {Sin[i 2 Pi/1000], Cos[i 2 Pi/1000], 0}], {i, step}];
circlerolled = 
Translate[circle1, 

2 {Sin[ 2 Pi step/1000], Cos[ 2 Pi step/1000], 0}]; 
Graphics3D[{fin, circlebase, circlerolled}, 
PlotRange -> {{-3.1, 3.1}, {-3.1, 3.1}, {-0.1, 0.1}}, 
ViewPoint -> {0, 0, 1}, Boxed -> False],
{step, 1, 1000}]

Second Cell:


Manipulate[
circle = ParametricPlot3D[{Sin[x], Cos[x], 0}, {x, -Pi, Pi}, 
PerformanceGoal -> "Quality"];

circle1 = First[circle];
circlebase = Scale[circle1, {-3, -3, -3}, {0, 0, 0}];
fin = Table[
Translate[
Rotate[Point[{-1, 0, 0}], - i 2 Pi/(251/(-2)), {0, 0, 1}], 
 -2 {Sin[i 2 Pi/251], Cos[i 2 Pi/251], 0}], {i, step}];
circlerolled = 
Translate[
circle1, (-3 + 1) {Sin[ 2 Pi step/251], Cos[ 2 Pi step/251], 0}]; 
Graphics3D[{fin, circlebase, circlerolled}, 

PlotRange -> {{-3, 3}, {-3, 3}, {-0.1, 0.1}}, 
ViewPoint -> {0, 0, 1}, Boxed -> False],
{step, 1, 251}]

The code itself should produce this after executing them separately.If you are not able to produce it, you may try to download my sample notebook.


https://drive.google.com/file/d/0B6gQp_HcIW0ZVmwyeUJHR0MtM0U/view?usp=sharing


I guarantee it is not malicious (anyway you can open it with a text editor and see the source code)



Answer



This infinite evaluation is the result of "cross-linking" the two Dynamic expressions due to the failure to localize your Symbols with DynamicModule, e.g.:


DynamicModule[{circle, circle1, circlebase, fin, circlerolled},

 Manipulate[
  circle = ParametricPlot3D[{Sin[x], Cos[x], 0}, {x, -Pi, Pi}, 
    PerformanceGoal -> "Quality"];
  circle1 = First[circle];
  circlebase = Scale[circle1, {1, 1, 1}, {0, 0, 0}];
  fin = Table[
    Translate[Rotate[{Point[{-1, 0, 0}]}, -i 4 Pi/1000, {0, 0, 1}], 
     2 {Sin[i 2 Pi/1000], Cos[i 2 Pi/1000], 0}], {i, step}];
  circlerolled = Translate[circle1, 2 {Sin[2 Pi step/1000], Cos[2 Pi step/1000], 0}];
  Graphics3D[{fin, circlebase, circlerolled}, 

   PlotRange -> {{-3.1, 3.1}, {-3.1, 3.1}, {-0.1, 0.1}}, ViewPoint -> {0, 0, 1}, 
   Boxed -> False], {step, 1, 1000}
 ]
]



  • step is automatically localized by Manipulate and does not need to be added to the DynamicModule specification.





  • This localization should be included for all Manipulate expressions unless you have specific need to access the values globally, and if you do you will need unique Symbol names.




Comments

Post a Comment

Popular posts from this blog

front end - keyboard shortcut to invoke Insert new matrix

I frequently need to type in some matrices, and the menu command Insert > Table/Matrix > New... allows matrices with lines drawn between columns and rows, which is very helpful. I would like to make a keyboard shortcut for it, but cannot find the relevant frontend token command (4209405) for it. Since the FullForm[] and InputForm[] of matrices with lines drawn between rows and columns is the same as those without lines, it's hard to do this via 3rd party system-wide text expanders (e.g. autohotkey or atext on mac). How does one assign a keyboard shortcut for the menu item Insert > Table/Matrix > New... , preferably using only mathematica? Thanks! Answer In the MenuSetup.tr (for linux located in the $InstallationDirectory/SystemFiles/FrontEnd/TextResources/X/ directory), I changed the line MenuItem["&New...", "CreateGridBoxDialog"] to read MenuItem["&New...", "CreateGridBoxDialog", MenuKey["m", Modifiers-...
Post a Comment
Read more

How to thread a list

I have data in format data = {{a1, a2}, {b1, b2}, {c1, c2}, {d1, d2}} Tableform: I want to thread it to : tdata = {{{a1, b1}, {a2, b2}}, {{a1, c1}, {a2, c2}}, {{a1, d1}, {a2, d2}}} Tableform: And I would like to do better then pseudofunction[n_] := Transpose[{data2[[1]], data2[[n]]}]; SetAttributes[pseudofunction, Listable]; Range[2, 4] // pseudofunction Here is my benchmark data, where data3 is normal sample of real data. data3 = Drop[ExcelWorkBook[[Column1 ;; Column4]], None, 1]; data2 = {a #, b #, c #, d #} & /@ Range[1, 10^5]; data = RandomReal[{0, 1}, {10^6, 4}]; Here is my benchmark code kptnw[list_] := Transpose[{Table[First@#, {Length@# - 1}], Rest@#}, {3, 1, 2}] &@list kptnw2[list_] := Transpose[{ConstantArray[First@#, Length@# - 1], Rest@#}, {3, 1, 2}] &@list OleksandrR[list_] := Flatten[Outer[List, List@First[list], Rest[list], 1], {{2}, {1, 4}}] paradox2[list_] := Partition[Riffle[list[[1]], #], 2] & /@ Drop[list, 1] RM[list_] := FoldList[Transpose[{First@li...
Post a Comment
Read more

mathematical optimization - Minimizing using indices, error: Part::pkspec1: The expression cannot be used as a part specification

I want to use Minimize where the variables to minimize are indices pointing into an array. Here a MWE that hopefully shows what my problem is. vars = u@# & /@ Range[3]; cons = Flatten@ { Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; Minimize[{Total@((vec1[[#]] - vec2[[u[#]]])^2 & /@ Range[1, 3]), cons}, vars, Integers] The error I get: Part::pkspec1: The expression u[1] cannot be used as a part specification. >> Answer Ok, it seems that one can get around Mathematica trying to evaluate vec2[[u[1]]] too early by using the function Indexed[vec2,u[1]] . The working MWE would then look like the following: vars = u@# & /@ Range[3]; cons = Flatten@{ Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; NMinimize[ {Total@((vec1[[#]] - Indexed[vec2, u[#]])^2 & /@ R...
Post a Comment
Read more