2.28.2 Greatest hits from previous weeks

2.28.2.1 Multivariable Taylor expansion does not work as expected
2.28.2.2 How to calculate scalar curvature Ricci tensor and Christoffel symbols in Mathematica?
2.28.2.3 How to create effect like Van Gogh’s stroke brush?
2.28.2.4 How to perform a multi-peak fitting?
2.28.2.5 What are the most common pitfalls awaiting new users?
2.28.2.6 How to find integer solutions?
2.28.2.7 LaTeXand Mathematica
2.28.2.1 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  ...

asked by matheorem https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=4742 55 votes

answered by Jens https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=245 61 votes

2.28.2.2 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, I run into the following error:

asked by Zoe Rowa https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1713 36 votes

answered by Yi-Zen Chu https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=4869 17 votes

2.28.2.3 How to create effect like Van Gogh’s stroke brush?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=39003

I need to apply Van Gogh’s stroke brush effect to a random image

Take the following image as an example:

Thank you so much if you could help!

asked by user10495 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=10495 33 votes

answered by Simon Woods https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=862 51 votes

2.28.2.4 How to perform a multi-peak fitting?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=26336

I am wondering how to implement the multi-peak detecting and fitting in Mathematica. Following is an example of fitting the data using three peaks (such that the data ~ peak1 + peak2 + peak3).

The ...

asked by Everett You https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1389 54 votes

answered by Silvia https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=17 54 votes

2.28.2.5 What are the most common pitfalls awaiting new users?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=18393

As you may already know, Mathematica is a wonderful piece of software. However, it has a few characteristics that tend to confuse new (and sometimes not-so-new) users. That can be clearly seen from ...

asked by Dr. belisarius https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=193 460 votes

answered by Michael E2 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=4999 277 votes

2.28.2.6 How to find integer solutions?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=42359

Following is the equation:

Need to solve for integer values of x,y when a,b lies between -1000 and 1000. Problem is to find the number of integer values of pair (x,y) that satisfy it.

asked by Sahil Sareen https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=12396 2 votes

answered by bill s https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1783 4 votes

2.28.2.7 LaTeXand Mathematica

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=736

I quite often would like to draw graphics in my LaTeXdocuments using Mathematica. I have encountered three problems. I would like to know if there are any workarounds to these problems

I would ...

asked by Thomas Rot https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=227 124 votes

answered by Simon https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=34 45 votes