7.11.1 Top new questions this week

7.11.1.1 Head[x] vs x[[0]]

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=242183

Can we say Head[x] and x[[0]] are identical ? 
In mathematica manual I could find : 'The head is the part with index 0' 
 
But I am not sure whether Head[x] are x[[0]] are really interchangeable in any ... 
[list-manipulation] [built-in-symbols] [head]
 

asked by imida k https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=34532 15 votes

answered by Leonid Shifrin https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=81 13 votes

7.11.1.2 How to roll a graph on the y-axis

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=242180

I want to roll the function f(x)=sqrt(x), x[0,1] along the y-axis. 
I know how to rotate the graph around a point, but I'm not sure how to rotate along an axis in 2D. 
Rotating around a point e.g. (0,... 
[matrix] [rotation]
 

asked by Guy Foxx https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=75736 14 votes

answered by cvgmt https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=72111 17 votes

7.11.1.3 Numerically solving Helmholtz equation in 2D for a Guitar

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=242138

Hi I am new to using Mathematica, so am not too confident. I am essentially trying to model vibrations of a guitar sound board for a project. It would be great to get some visualisations of the ... 
[differential-equations] [numerics] [finite-element-method]
 

asked by sp96 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=77970 11 votes

answered by Tim Laska https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=61809 8 votes

7.11.1.4 How to draw the tree in a "pitchfork" form?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=242140

How to set the options or other parameters in a TreePlot to draw the branching outside of the vertex? I.e. in a form similar to a dendrogram (but the dendrogram plot itself does not support the ... 
[trees] [drawing]
 

asked by Slepecky Mamut https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=48033 10 votes

answered by kglr https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=125 9 votes

7.11.1.5 Digitizing a geometrical sensor

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=242186

I want to quantify the flow from photos taken from a sensor such as this one: 
 
For a limited number of readings, I can use a plot digitization method. However, I need to do this many times for ... 
[image-processing] [computational-geometry] [digitization] [morphologicalcomponents]
 

asked by MathX https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=38575 9 votes

answered by MelaGo https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=63360 10 votes

7.11.1.6 How Can I Compute The Automorphism Group of a Matroid?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=242030

I want to compute the automorphism group of a matroid. This reduces to the following (more general) problem: 
Suppose I have a list of sets $\{\{b_{11},\dots,b_{1k}\},\dots,\{b_{k1},\dots,b_{kk}\}\}$ ... 
[list-manipulation] [group-theory]
 

asked by Madeline Brandt https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=51040 7 votes

answered by Madeline Brandt https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=51040 6 votes

7.11.1.7 How to make a circular heat map or diagram in Mathematica?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=242425

Is there any way to make a circular heat map in Mathematica? 
Thanks for your help! 
Here is a toy example for regular heat map. Can anyone help me make it to a circular one? 
... 
[plotting] [visualization]
 

asked by Frankie https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=70269 6 votes

answered by kglr https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=125 4 votes