7.35.2 Greatest hits from previous weeks

7.35.2.1 Mathematica 10.0.x freezes in Initializing kernels

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=92931

Bug caused by paclet update and fixed by paclet update. 
I updated to Windows 10 and have been running Mathematica fine on it for over a month.  For some reason, it has just stopped working. I don't ... 
[bugs] [front-end] [system] [kernel-startup] [paclets]
 

asked by mitcheljh https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=6783 80 votes

answered by ilian https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=145 101 votes

7.35.2.2 How to calculate scalar curvature, Ricci tensor and Christoffel symbols in Mathematica?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=8895

I am seeking a convenient and effective way to calculate such geometric quantities. I've used packages like  TensoriaCalc , but they don't work at all time. Sometimes,... 
[symbolic] [physics] [tensors] [differential-geometry]
 

asked by Zoe Rowa https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1713 45 votes

answered by Yi-Zen Chu https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=4869 21 votes

7.35.2.3 Finding unit tangent, normal, and binormal vectors for a given r(t)

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=18598

For my Calc III class, I need to find $T(t), N(t)$, and $B(t)$ for $t=1, 2$, and $-1$, given $r(t)=\{t,t^2,t^3\}$. 
 
I've got Mathematica, but I've never used it before and I'm not sure how to coerce ... 
[equation-solving] [calculus-and-analysis] [geometry] [vector-calculus] [homework]
 

asked by a98 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=5605 32 votes

answered by Artes https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=184 46 votes

7.35.2.4 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 43 votes

answered by Artes https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=184 65 votes

7.35.2.5 How can I create an empty JSON object?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=50727

For creating non-empty object, I use following syntax 
 
 ExportString[{"key" -> "value"}, "JSON"] 
(*{"key" : "value"}*) 
 
 
But how can I create an empty object? ... 
[export] [conversion] [json-format]
 

asked by molekyla777 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=11981 10 votes

answered by jkuczm https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=14303 11 votes

7.35.2.6 Entering numbers in Scientific Notation?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=36792

I need to play with a lot of powers such as  10^-3 .  1E-3  does not work for it. Is there any short form for it? 
[number-representation]
 

asked by hhh https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=2000 67 votes

answered by Joe https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=44710 1 vote

7.35.2.7 What do the X and Y axis stand for in the Fourier transform domain?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=85139

In Wolfram Mathematica the function  Fourier  has the following declaration 
 
 Fourier[list] 
 
 
And after a list is given to the ... 
[numerics] [fourier-analysis] [faq]
 

asked by user253956 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=29958 28 votes

answered by Hugh https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=12558 64 votes