4.40.1 Top new questions this week

4.40.1.1 Is building an event-based parser possible/reasonable in Mathematica (WL)?

https://mathematica.stackexchange.com/questions/157834/is-building-an-event-based-parser-possible-reasonable-in-mathematica-wl

 
Too long? Go to Problems section 
 
Background 
 
I like to learn by doing small, sometimes artificial, projects. Among other things I had 'parsers', and 'stream methods / streams in MMA' on my to learn  ...
 

- asked by Kuba 11votes

4.40.1.2 Test if a list is a constant integer multiple of another list

https://mathematica.stackexchange.com/questions/157783/test-if-a-list-is-a-constant-integer-multiple-of-another-list

 
I have a list of lists, and I want to eliminate all the lists that are constant integer multiples of another list. My initial approach was to divide the lists using nested tables. 
 
ex1 = {{1, 1, 1},  ...
 

- asked by Lokdal (10 votes), answered by Mr.Wizard (9 votes)

4.40.1.3 Cannot Reproduce Answer to 99576

https://mathematica.stackexchange.com/questions/157889/cannot-reproduce-answer-to-99576

 
Bug introduced between versions 10.1 and 10.4, and persisting through 11.2.  Reported to Wolfram, Inc as CASE:3958778. 
 
Using either 11.2 or 10.4 on Windows 10 (64 bit), I am unable to reproduce the  ...
 

- asked by bbgodfrey 9votes

4.40.1.4 Does `SeedRandom` give the same set of random numbers across operating systems?

https://mathematica.stackexchange.com/questions/157621/does-seedrandom-give-the-same-set-of-random-numbers-across-operating-systems

 
If I use 
 
SeedRandom[12345] 
RandomReal[{0,1},100] 
 
 
I get the same random numbers on two versions of Mathematica:  10.4.1.0 on Windows 10 and 11.1.1.0 on Windows 7. 
 
But does the same seed get the  ...
 

- asked by JimB (9 votes), answered by halirutan (8 votes)

4.40.1.5 Fill the data of an Association based on a list

https://mathematica.stackexchange.com/questions/157852/fill-the-data-of-an-association-based-on-a-list

 
Consider the following the list and association. 
 
list1 = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; 
asc = <|1 -> a, 4 -> b, 7 -> c, 10 -> d|>; 
 
 
I would like to create an association which  ...
 

- asked by Anjan Kumar (7 votes), answered by Kuba (5 votes)

4.40.1.6 How to extract data points from two graphics and find the intersections between them?

https://mathematica.stackexchange.com/questions/157787/how-to-extract-data-points-from-two-graphics-and-find-the-intersections-between

 
I am working on a mathematical problem called "Buffon's Needle". Here is the setup I made: 
 
point[v_, u_] := Normalize[v - u] + u 
 
experiment50 = Show[ 
Graphics[ 
Table[{ 
RGBColor[0, 0, 0], 
...
 

- asked by Anna Morales Melgares (7 votes), answered by kglr (7 votes)

4.40.1.7 How to thread over ragged list while skipping empty sub-lists?

https://mathematica.stackexchange.com/questions/157635/how-to-thread-over-ragged-list-while-skipping-empty-sub-lists

 
I have a very large ragged list result that is a list of list of pairs where sometimes the sub-list contains the empty list. 
 
res = {{{20, 1}, {200, 2}}, {{}}, {{175, 1}}}; 
 
 
In the above minimal  ...
 

- asked by Edmund (7 votes), answered by kglr (9 votes)