output formatting - Symbol with Subscript but no quotes in it!

If I use the following function to define me a fancy subscript:

Needs["Notation`"];
Symbolize[ParsedBoxWrapper[SubscriptBox["_", "_"]]]

SetAttributes[fancySubscript,HoldFirst]

fancySubscript[var_Symbol, tag_String, index_Integer] /;
  Not[ValueQ[var]] := Subscript[var, tag <> ToString[index]]


fancySubscript[var_Symbol, tags : {_String ..}, index_Integer] /; 
  Not[ValueQ[var]] := fancySubscript[var, #, index] & /@ tags

fancySubscript[var_Symbol, tags : {_String ..}, indices : {_Integer ..}] /; 
  Not[ValueQ[var]] := fancySubscript[var, tags, #] & /@ indices

I can use the following now:

fancySubscript[b, {"b"}, Range@3]

$\left( \begin{array}{c} b_{\text{b1}} \\ b_{\text{b2}} \\ b_{\text{b3}} \\ \end{array} \right)$

With the notation module by symbolizing the subscripts: the values are now :

b\[UnderBracket]Subscript\[UnderBracket]DoubleQuote\[UnderBracket]b1\[UnderBracket]DoubleQuote

1. Problem
But when I want to refer to such a variable in the list above and write with the shortcuts in a cell by typing b then Ctrl+_ then 1.

The variable is a new symbol because i did not use Quotes ""

b\[UnderBracket]Subscript\[UnderBracket]b1

How can we circumvent this that I can still write all variables in the cell and they are parsed and interpreted as the one defined in the fancySubscript command?

It is not so easy because, when I would use something like this:

fancySubscript[b, {b}, Range@3]

I would get an infinite loop, because it is no more a string, hm...

2. Problem:

I cannot assign it back to the variable b:

 b=fancySubscript[b, {"b"}, Range@3]

This gives an infinite loop, but when I try this:

btemp=fancySubscript[b, {"b"}, Range@3]
b=btemp

This should work, and not give an inifinte loop, because btemp contains the new defined symbols and they should then be assigned to b again, but also here mathematica trys to run a recursion which I dont understand??

Comments

plotting - Filling between two spheres in SphericalPlot3D

Manipulate[ SphericalPlot3D[{1, 2 - n}, {θ, 0, Pi}, {ϕ, 0, 1.5 Pi}, Mesh -> None, PlotPoints -> 15, PlotRange -> {-2.2, 2.2}], {n, 0, 1}] I cant' seem to be able to make a filling between two spheres. I've already tried the obvious Filling -> {1 -> {2}} but Mathematica doesn't seem to like that option. Is there any easy way around this or ... Answer There is no built-in filling in SphericalPlot3D . One option is to use ParametricPlot3D to draw the surfaces between the two shells: Manipulate[ Show[SphericalPlot3D[{1, 2 - n}, {θ, 0, Pi}, {ϕ, 0, 1.5 Pi}, PlotPoints -> 15, PlotRange -> {-2.2, 2.2}], ParametricPlot3D[{ r {Sin[t] Cos[1.5 Pi], Sin[t] Sin[1.5 Pi], Cos[t]}, r {Sin[t] Cos[0 Pi], Sin[t] Sin[0 Pi], Cos[t]}}, {r, 1, 2 - n}, {t, 0, Pi}, PlotStyle -> Yellow, Mesh -> {2, 15}]], {n, 0, 1}]

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}]

plotting - Adding a thick curve to a regionplot

Suppose we have the following simple RegionPlot: f[x_] := 1 - x^2 g[x_] := 1 - 0.5 x^2 RegionPlot[{y < f[x], f[x] < y < g[x], y > g[x]}, {x, 0, 2}, {y, 0, 2}] Now I'm trying to change the curve defined by $y=g[x]$ into a thick black curve, while leaving all other boundaries in the plot unchanged. I've tried adding the region $y=g[x]$ and playing with the plotstyle, which didn't work, and I've tried BoundaryStyle, which changed all the boundaries in the plot. Now I'm kinda out of ideas... Any help would be appreciated! Answer With f[x_] := 1 - x^2 g[x_] := 1 - 0.5 x^2 You can use Epilog to add the thick line: RegionPlot[{y < f[x], f[x] < y < g[x], y > g[x]}, {x, 0, 2}, {y, 0, 2}, PlotPoints -> 50, Epilog -> (Plot[g[x], {x, 0, 2}, PlotStyle -> {Black, Thick}][[1]]), PlotStyle -> {Directive[Yellow, Opacity[0.4]], Directive[Pink, Opacity[0.4]],

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