Skip to main content

dynamic - How to create a notebook element that can replace itself?


I would like to create a notebook element that can replace itself.


Here's an example to illustrate:


Panel[Column[
{Style["This is a panel", Bold],
Button["Press me!",
SelectionMove[EvaluationNotebook[], All, EvaluationCell];
NotebookWrite[EvaluationNotebook[],
"\"Now I'm just a piece of static text.\""]]}]]


This code will create a little panel:


Mathematica graphics


If we press the button, the panel will get replaced by a piece of static text (i.e. not a dynamic expression that's shown as text, but just plain old non-dynamic text).


Mathematica graphics


Well, in this implementation actually it's not the panel that gets replaced, but the complete cell containing the panel, and that's my problem: I need only the panel to be replaced, so this will work even if the panel is just a subexpression in a larger expression.


How can we create an UI control that is able to replace itself with an arbitrary expression in the notebook?



Answer



This solution relies on putting a TagBox with a custom tag around the part to be replaced, reading the cell and replacing the tag, then writing it back. Personally I've always felt that the need to read the entire cell and write it all again seems kind of clunky, but I don't know of a better way to do this.


MakeBoxes[replacementMarker[a_,tag_],StandardForm]^:=TagBox[MakeBoxes[a],tag]


replaceMark[rule_,nb_:EvaluationNotebook[],which_:All,cell_:EvaluationCell]:=(
SelectionMove[nb,which,cell];
NotebookWrite[EvaluationNotebook[],NotebookRead[EvaluationNotebook[]]/.rule])

Row[{"Not replaced",
replacementMarker[
Panel[Column[{Style["This is a panel",Bold],Button["Press me!",
replaceMark[TagBox[_,"replacementTag"] :> MakeBoxes["\" Now I'm just text. \""]]
]}]]
,"replacementTag"]

,"Not replaced"}]

Important note! The action cannot be undone, so if used for example to allow dynamic reformatting of data or similar, be aware that mistakes can end up deleting the old contents.


Comments

Popular posts from this blog

functions - Get leading series expansion term?

Given a function f[x] , I would like to have a function leadingSeries that returns just the leading term in the series around x=0 . For example: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x)] x and leadingSeries[(1/x + 2 + (1 - 1/x^3)/4)/(4 + x)] -(1/(16 x^3)) Is there such a function in Mathematica? Or maybe one can implement it efficiently? EDIT I finally went with the following implementation, based on Carl Woll 's answer: lds[ex_,x_]:=( (ex/.x->(x+O[x]^2))/.SeriesData[U_,Z_,L_List,Mi_,Ma_,De_]:>SeriesData[U,Z,{L[[1]]},Mi,Mi+1,De]//Quiet//Normal) The advantage is, that this one also properly works with functions whose leading term is a constant: lds[Exp[x],x] 1 Answer Update 1 Updated to eliminate SeriesData and to not return additional terms Perhaps you could use: leadingSeries[expr_, x_] := Normal[expr /. x->(x+O[x]^2) /. a_List :> Take[a, 1]] Then for your examples: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x), x] leadingSeries[Exp[x], x] leadingSeries[(1/x + 2 + (1 - 1/x...

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...

plotting - Plot 4D data with color as 4th dimension

I have a list of 4D data (x position, y position, amplitude, wavelength). I want to plot x, y, and amplitude on a 3D plot and have the color of the points correspond to the wavelength. I have seen many examples using functions to define color but my wavelength cannot be expressed by an analytic function. Is there a simple way to do this? Answer Here a another possible way to visualize 4D data: data = Flatten[Table[{x, y, x^2 + y^2, Sin[x - y]}, {x, -Pi, Pi,Pi/10}, {y,-Pi,Pi, Pi/10}], 1]; You can use the function Point along with VertexColors . Now the points are places using the first three elements and the color is determined by the fourth. In this case I used Hue, but you can use whatever you prefer. Graphics3D[ Point[data[[All, 1 ;; 3]], VertexColors -> Hue /@ data[[All, 4]]], Axes -> True, BoxRatios -> {1, 1, 1/GoldenRatio}]