8.30.2 Greatest hits from previous weeks

8.30.2.1 Why round to even integers?
8.30.2.2 Standard deck of 52 playing cards in curated data?
8.30.2.3 Finding Limits in several variables
8.30.2.4 xkcd-style Plots
8.30.2.5 How to make an inkblot?
8.30.2.6 Multivariable Taylor expansion does not work as expected
8.30.2.7 QR Code in shopping cart handle
8.30.2.1 Why round to even integers?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=2116

According to the Mathematica help: 
Round rounds numbers of the form x.5 toward the nearest even integer. 
For example: 
 
 Round[{0.5, 1.5, 2.5, 3.5, 4.5}] 
 
 
gives 
... 
[numerics] [language-design]
 
asked by wxffles https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=427 Score of 83
answered by Per Alexandersson https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=488 Score of 51
8.30.2.2 Standard deck of 52 playing cards in curated data?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=16108

I am not sure how to find out what all is included as curated data. For example, are the individual images of each of the 52 cards in a standard deck of playing cards included? 
 
If not, is there a way ... 
[curated-data]
 
asked by JohnD https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1629 Score of 26
answered by rm -rf https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=5 Score of 24
8.30.2.3 Finding Limits in several variables

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=21544

Is there a way to find a limit of a multivariable function, like 
 
$$\lim_{(x,y)\to (0,0)} f(x,y)$$ 
with Mathematica? 
 
When $f$ is continuous, we can use 
$$\lim_{(x,y)\to (0,0)} f(x,y)=\lim_{(x,0)\... 
[functions] [calculus-and-analysis]
 
asked by Dominic Michaelis https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=5899 Score of 32
answered by whuber https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=91 Score of 42
8.30.2.4 xkcd-style Plots

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=11350

I received an email to which I wanted to respond with a xkcd-style graph, but I couldn't manage it. Everything I drew looked perfect, and I don't have enough command over ... 
[plotting] [generative-art]
 
asked by Amatya https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=2039 Score of 635
answered by Simon Woods https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=862 Score of 499
8.30.2.5 How to make an inkblot?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=3345

How to effectively create a polygon that looks like a realistic inkblot? So far, I could come up with this (borrowing from Ed Pegg Jr.'s Rorschach demonstration): 
 
... 
[graphics] [performance-tuning] [image-processing] [generative-art]
 
asked by István Zachar https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=89 Score of 89
answered by Sjoerd C. de Vries https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=57 Score of 52
8.30.2.6 Multivariable Taylor expansion does not work as expected

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=15023

The basic multivariable Taylor expansion formula around a point is as follows: 
 
$$ 
f(\mathbf r + \mathbf a) = f(\mathbf r) + (\mathbf a \cdot \nabla )f(\mathbf r) + \frac{1}{2!}(\mathbf a \cdot \nabla)... 
[calculus-and-analysis] [series-expansion]
 
asked by matheorem https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=4742 Score of 74
answered by Jens https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=245 Score of 81
8.30.2.7 QR Code in shopping cart handle

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=26268

This week, the market people from my work wanted to put QR codes in shopping cart handles, but when they tested it, the QR code did not work. I noted that the cylindrical curvature (even small) ... 
[image-processing]
 
asked by Murta https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=2266 Score of 201
answered by halirutan https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=187 Score of 196