4.29.1 Top new questions this week

4.29.1.1 String operation 1000X slower for special characters

https://mathematica.stackexchange.com/questions/152293/string-operation-1000x-slower-for-special-characters

 
It seems that the string operation is very slow if we have special characters in the string. Consider this example, 
 
str = 
StringJoin@ 
RandomChoice[Join[Alphabet[], ToString /@ Range[0, 9]],  ...
 

- asked by xslittlegrass (12 votes), answered by Alexey Popkov (12 votes)

4.29.1.2 Making a website with Mathematica

https://mathematica.stackexchange.com/questions/152663/making-a-website-with-mathematica

 
I know many people here have various websites associated with them and I'm guessing do at least some of the development of that stuff in Mathematica. 
 
I recently fell down that rabbit hole myself,  ...
 

- asked by b3m2a1 (11 votes), answered by C. E. (9 votes)

4.29.1.3 Convert association with list key to nested assocations

https://mathematica.stackexchange.com/questions/152676/convert-association-with-list-key-to-nested-assocations

 
I have an association that maps {x, y} pairs to values, for example: 
 
<|{0, 0} -> "a", {-1, -4} -> "b", {-1, 1} -> "c", {-1, 0} -> "d", {1, 0} -> "e"|> 
 
 
I want to convert this  ...
 

- asked by 2012rcampion (9 votes), answered by MarcoB (8 votes)

4.29.1.4 Matching (y/x)^u terms wherever the appear in an expression

https://mathematica.stackexchange.com/questions/152559/matching-y-xu-terms-wherever-the-appear-in-an-expression

 
Mathematica keeps rewriting expressions, so it is hard to figure what pattern to use. 
 
I am trying to replace all occurrences of $\frac{y}{x}$ by $t$, but Mathematica re-writes  ...
 

- asked by Nasser (9 votes), answered by aardvark2012 (4 votes)

4.29.1.5 Bulletproofing packages against SetOptions of built-ins

https://mathematica.stackexchange.com/questions/152472/bulletproofing-packages-against-setoptions-of-built-ins

 
Packages are (obviously) written in terms of built-in Mathematica functions.  But many (if not, most) of these functions have options, like Expand, Solve, Compile 
 
While a package is active, the user  ...
 

- asked by QuantumDot (9 votes), answered by Leonid Shifrin (12 votes)

4.29.1.6 How can I offset a curve from the given data points?

https://mathematica.stackexchange.com/questions/152298/how-can-i-offset-a-curve-from-the-given-data-points

 
I am new to Mathematica programming. 
 
I have a question related to my work with this software. 
 
I have the data points below: 
 
{{128.011, 86.7748}, {128.011, 86.7748}, {128.167, 86.7663}, {128.19,  ...
 

- asked by Mukidi Lee (8 votes), answered by J. M. (12 votes)

4.29.1.7 Export[..., "tsv"] drops minus signs from Dataset [horrific bug?]

https://mathematica.stackexchange.com/questions/152355/export-tsv-drops-minus-signs-from-dataset-horrific-bug

 
Toy example: 
 
First, create a Dataset: 
 
data = Dataset[{<|"x" ->  1, "y" -> -2|>, 
<|"x" -> -3, "y" ->  4|>}] 
 
 
 
 
 
 
Next, export it as a TSV file: 
 
...
 

- asked by kjo (8 votes), answered by Rolf Mertig (6 votes)