4.48.1 Top new questions this week

4.48.1.1 Why does Mathematica results differ from C++ results within machine precision?

https://mathematica.stackexchange.com/questions/161716/why-does-mathematica-results-differ-from-c-results-within-machine-precision

 
I am trying to wrap my head around floating-point precision. Performing the following numeric operation: 
 
275./6.*1.03692775514337 
 
 
in Mathematica and C++ and taking the difference of the two results  ...
 

- asked by Knowledge (22 votes), answered by ilian (44 votes)

4.48.1.2 Bug with Block & Lookup: Scope Variable Leak

https://mathematica.stackexchange.com/questions/161616/bug-with-block-lookup-scope-variable-leak

 
After debugging a large chunk of code, I could identify this MWE. 
 
ClearAll@test 
test[var_String]:= Block[{association}, 
association = <|"x"-> <|"key01"-> "ok"|>|>[var]; 
...
 

- asked by Murta (22 votes), answered by Albert Retey (15 votes)

4.48.1.3 Why is "k" in the output of Sum[Log[k]/k^k,  k,1,Infinity ]?

https://mathematica.stackexchange.com/questions/161704/why-is-k-in-the-output-of-sumlogk-kk-k-1-infinity

 
NSum[Log[k]/k^k, {k,1,Infinity}, WorkingPrecision->50] 
(* 0.219947267975228664843531307905860703797097130 *) 
 
 
But 
 
Sum[Log[k]/k^k, {k,1,Infinity}] 
(* -(PolyLog^(1,0))[0,1/k] *) 
 
 
What does "k" in  ...
 

- asked by Vaclav Kotesovec 13votes

4.48.1.4 Simulating molecular dynamics efficiently

https://mathematica.stackexchange.com/questions/161471/simulating-molecular-dynamics-efficiently

 
The following website offers a very nice molecular dynamics simulation:http://physics.weber.edu/schroeder/md/. It is pretty neat and quite a few physical phenomena can be described from that small  ...
 

- asked by anderstood (13 votes), answered by Henrik Schumacher (16 votes)

4.48.1.5 Why is listable not an attribute of the Set function?

https://mathematica.stackexchange.com/questions/161428/why-is-listable-not-an-attribute-of-the-set-function

 
The following is a list of attributes for the Set function: 
 
Attributes[Set] 
 
 
 
{HoldFirst, Protected, SequenceHold} 
 
 
 
Why is Listable not included?
 

- asked by S.V (13 votes), answered by Kuba (16 votes)

4.48.1.6 How to improve quality of this Plot3D

https://mathematica.stackexchange.com/questions/161771/how-to-improve-quality-of-this-plot3d

 
I tried driving up PlotPoints and MaxRecursion but the intersections look weird, is there some other trick I can do? 
 
plot = Plot3D @@ {Abs[Sqrt[x] + Sqrt[y]] /. {x -> Sin[2 x], 
y -> Cos[2  ...
 

- asked by Yaroslav Bulatov (10 votes), answered by Nasser (11 votes)

4.48.1.7 How can I tell Mathematica to interpret 0xffff as a hexadecimal number?

https://mathematica.stackexchange.com/questions/161646/how-can-i-tell-mathematica-to-interpret-0xffff-as-a-hexadecimal-number

 
I am stuck. I would like Mathematica simply accept 0x as a prefix Operator for Hexadecimal Numbers. I know that 0x is interpreted as 0*x, so maybe this is just not possible. I am a programmer and am  ...
 

- asked by Mark (9 votes), answered by Carl Woll (16 votes)