9.35.2 Greatest hits from previous weeks

9.35.2.1 Where can I find examples of good Mathematica programming practice?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=18

I consider myself a pretty good Mathematica programmer, but I'm always looking out for ways to either improve my way of doing things in Mathematica, or to see if there's something nifty that I haven't ... 
[reference-request] [programming]
 

asked by J. M.'s eventual burnout https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=50 Score of 596

answered by faysou https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=66 Score of 523

9.35.2.2 How to find the position of elements in a list satisfying criteria

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=180

Say I have a list  x={2,4,6,8,10}  and I want to find out the positions of the elements that are greater than 7. 
 
... 
[list-manipulation]
 

asked by PeterR https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=140 Score of 72

answered by J. M.'s eventual burnout https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=50 Score of 74

9.35.2.3 Is it possible to export the equations from Mathematica to MATLAB?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=14035

Is it possible to export the output expressions from Mathematica computations (e.g., equations) in valid MATLAB syntax? 
[export] [matlab]
 

asked by Seyhmus Güngören https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=4256 Score of 47

answered by rm -rf https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=5 Score of 51

9.35.2.4 How to add a vertical line to a plot

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=3561

In the plot below I would like to add two vertical lines at $x = \frac{\pi}{15} \pm \frac{1}{20}$. 
How can I do that? 
 
... 
[plotting]
 

asked by sjdh https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=515 Score of 80

answered by Ajasja https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=745 Score of 98

9.35.2.5 1 Plot, 2 Scale/Axis

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=627

I would like to plot those two datasets on top of each other. But they have very different range on the $y$ axis. How can I have two different axis? 
 
I found the following on the help menu but quite ... 
[plotting] [customization]
 

asked by 500 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=172 Score of 160

answered by ArgentoSapiens https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=92 Score of 162

9.35.2.6 How to plot an ellipse?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=20100

I'm new to Mathematica, and I'm finding it difficult to plot an ellipse. 
I tried using 
 
 Plot[(x/5)^2 + (y/3)^2 == 1, {x, -5, 5}, {y, -3, 3}] 
 
 
but I'm getting ... 
[plotting]
 

asked by Sriram https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=6075 Score of 19

answered by Jens https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=245 Score of 33

9.35.2.7 Calling Correct Function for Plotting DiracDelta

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=3506

I am wondering what is the correct function in Mathematica to plot the true impulse function, better known as the  DiracDelta[]  function. When using this inside of a ... 
[plotting] [functions]
 

asked by night owl https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=116 Score of 19

answered by Heike https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=46 Score of 21