10.6.2 Greatest hits from previous weeks

10.6.2.1 How to plot an ellipse?
10.6.2.2 Image processing: Floor plan - detecting rooms' borders (area) and room names' texts
10.6.2.3 How to calculate contour integrals with Mathematica?
10.6.2.4 Get a "step-by-step" evaluation in Mathematica
10.6.2.5 How to find the position of elements in a list satisfying criteria
10.6.2.6 Calculating the normalization constant for a wavefunction
10.6.2.7 Using Export[] sends the file where?
10.6.2.1 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
10.6.2.2 Image processing: Floor plan - detecting rooms' borders (area) and room names' texts

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=19546

Here is a simple building floor plan. I would like to derive the rooms as (rectangular) components and the names of the rooms. This is very common representation of building floor plans. 
 
The problem 
 
... 
[image-processing]
 
asked by s.s.o https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=840 Score of 66
answered by Niki Estner https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=242 Score of 60
10.6.2.3 How to calculate contour integrals with Mathematica?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=34073

How to calculate the integral of $\frac{1}{\sqrt{4 z^2 + 4 z + 3}}$ over the unit circle counterclockwise for each branch of the integrand? 
[calculus-and-analysis] [complex]
 
asked by user64494 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=7152 Score of 45
answered by Artes https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=184 Score of 69
10.6.2.4 Get a "step-by-step" evaluation in Mathematica

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=148

Is it possible in Mathematica to get a step-by-step evaluation of some functions; that's to say, outputting not only the result but all the stages that have led to it? If so, how does one do it? 
 
... 
[evaluation] [interactive] [faq]
 
asked by Cydonia7 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=44 Score of 145
answered by J. M.'s eventual burnout https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=50 Score of 119
10.6.2.5 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 74
answered by J. M.'s eventual burnout https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=50 Score of 78
10.6.2.6 Calculating the normalization constant for a wavefunction

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=99248

How can I compute the normalization constant for a quantum mechanics wave-function, like $\Psi(x) = N \exp(-\lambda x^2/2)$ by using Mathematica? (The normalization constant is $N$). 
[physics]
 
asked by infiniteNOP https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=35524 Score of 2
answered by Jason B. https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=9490 Score of 5
10.6.2.7 Using Export[] sends the file where?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=8586

I am trying to use the  Export  command to convert a list of plots into a *.gif file, and the command runs and executes well, but I can't find the file! Where is it ... 
[export]
 
asked by Patrick Da Silva https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1785 Score of 49
answered by Vitaliy Kaurov https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=13 Score of 61