7.42.2 Greatest hits from previous weeks

7.42.2.1 How do I plot a plane EM wave?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=1987

I would like to display an electromagnetic (EM) wave.  I have written code that works, but it does not "shade" the area between the graph and the axes.  Both the ... 
[graphics] [physics] [visualization]
 

asked by Rainforest Frog https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=202 22 votes

answered by J. M. can't deal with it https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=50 16 votes

7.42.2.2 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

7.42.2.3 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 200 votes

answered by halirutan https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=187 194 votes

7.42.2.4 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=44 131 votes

answered by J. M. can't deal with it https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=50 112 votes

7.42.2.5 Is there something like DensityPlot3D to visualize atomic orbitals?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=32378

I'm visualizing some hydrogen like atomic orbitals.  For looking at plane slices of the probability density, the  DensityPlot  function works well, and with something ... 
[plotting] [physics] [chemistry]
 

asked by Peeter Joot https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=10 45 votes

answered by xslittlegrass https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1364 25 votes

7.42.2.6 Calculate the 2D Fourier transform of an Image

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=29203

I am new to Mathematica, and using version 8.0. 
 
I would like to calculate the 2D Fourier Transform of an  Image  with Mathematica and plot the magnitude and phase ... 
[image-processing] [image] [fourier-analysis]
 

asked by user8727 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=8727 19 votes

answered by Nasser https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=70 36 votes

7.42.2.7 Plotting Complex Quantity Functions

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=3458

Trying to plot with complex quantities seems not to work properly in what I want to accomplish. I would like to know if there is a general rule/way of plotting when you have complex counterparts in ... 
[plotting] [complex] [faq]
 

asked by night owl https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=116 43 votes

answered by Artes https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=184 29 votes