11.16.2 Greatest hits from previous weeks

11.16.2.1 How can I create an empty JSON object?
11.16.2.2 Drawing a square root spiral
11.16.2.3 Where can I find examples of good Mathematica programming practice?
11.16.2.4 How do I clear all user defined symbols?
11.16.2.5 Using Export[] sends the file where?
11.16.2.6 Plot, extract data to a file
11.16.2.7 How to perform a multi-peak fitting?
11.16.2.1 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 Score of 10
11.16.2.2 Drawing a square root spiral

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=66969

Here is a start. I'm looking for a nice way to draw it. 
 
... 
[graphics] [geometry]
 
asked by matrix42 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=5379 Score of 26
answered by Bob Hanlon https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=9362 Score of 25
11.16.2.3 Where can I find examples of good Mathematica programming practice?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=18

I consider myself a pretty good Mathematica programmer, but I'm always looking out for ways to either improve my way of doing things in Mathematica, or to see if there's something nifty that I haven't ... 
[reference-request] [programming]
 
asked by J. M.'s missing motivation https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=50 Score of 604
answered by faysou https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=66 Score of 528
11.16.2.4 How do I clear all user defined symbols?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=850

Is there some way to do this other than going to  Evaluation -> Quit kernel  and firing a new one up? 
[variable-definitions] [symbols] [faq] [clear] [persistence]
 
asked by niklasfi https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=82 Score of 115
answered by Artes https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=184 Score of 122
11.16.2.5 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 50
answered by Vitaliy Kaurov https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=13 Score of 61
11.16.2.6 Plot, extract data to a file

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=19859

I need to save data that Mathematica uses inside the  Plot  command. The format that I would like to have is: 
 
 x1 y1 
x2 y2 
..... 
 
 
... 
[plotting] [export]
 
asked by molkee https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=5097 Score of 37
answered by Mr.Wizard https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=121 Score of 55
11.16.2.7 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 ... 
[fitting] [data] [peak-detection]
 
asked by Everett You https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1389 Score of 58
answered by Silvia https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=17 Score of 57