I also found debugging was not easy during main tests. What you can do is, inside the body of each method, print messages that allow you to know first which method is called, and then whatever you're interested in (arguments received by the method, state of the list at the beginning, state of the list after applying the method...). This way you may find out which operation your code is not doing right.

Please use spoiler flag next time.

So I generally agree with the sentiment (especially with geometry/physics katas) but the sum of the first n numbers is such an important formula in the study of algorithms that I think it deserves its place here.

Total average is the average of all valid values:

discard = 2
array 0 = 800,1200,2100,4100,1300,700 // discard 800,1200 at start and 1300,700 at end
array 1 = 1000,1500,4500,5000,5800,2000,1500 // discard 1000,1500 at start and 2000,1500 at end

total avg = (2100 + 4100 + 4500 + 5000 + 5800) / 5

so true, after this kata i use filter with no math in

Exactly what it says in the description. Random lists are generated, random indexes are called, and random methods are used on the lists. This isn't unusual for a kata. If need be, test it locally. :)

I have no idea what is happening in random tests and how to debug them.

Man, this is a much clearer description

As I understood it [0, 4] are X coordinates and [0, 0] are corresponding Ys.

It's (0,4) not (4,0), order matters.

Python

logistic_map(5,2,[0,4],[0,0])
#returns
#[[0,1,2,1,0],
#[1,2,3,2,1]]

AFAIK Manhattan distance is calculated |x2-x1| + |y2-y1|.

So at (0,3) with supplys at (0,0) and (4,0) I got:

|0-0| + |0-3| = 3

and

|4-0| + |0-3| = 7

But the answer is 1. Did I misunderstand something? TIA.

  [[64, 63, 3, 4, 5, 6, 58, 57], 
   [56, 55, 11, 12, 13, 14, 50, 49], 
   [17, 18, 46, 45, 44, 43, 23, 24], 
   [25, 26, 38, 37, 36, 35, 31, 32], 
   [33, 34, 30, 29, 28, 27, 39, 40], 
   [41, 42, 22, 21, 20, 19, 47, 48], 
   [16, 15, 51, 52, 53, 54, 10, 9], 
   [8, 7, 59, 60, 61, 62, 2, 1]] 
   
   should equal 
   
   [[64, 2, 3, 61, 60, 6, 7, 57], 
    [9, 55, 54, 12, 13, 51, 50, 16], 
    [17, 47, 46, 20, 21, 43, 42, 24], 
    [40, 26, 27, 37, 36, 30, 31, 33], 
    [32, 34, 35, 29, 28, 38, 39, 25], 
    [41, 23, 22, 44, 45, 19, 18, 48], 
    [49, 15, 14, 52, 53, 11, 10, 56], 
    [8, 58, 59, 5, 4, 62, 63, 1]]

AFAICT that is also a magic square. So why isn't it an acceptable answer?

I can't agree more on that mate!

Python,

Testing for: s=TyTYLX TtEheF xXm MOXruUK bNZU, n=3
'tyTYLXTtEheFXXMMOXruUKBNZu' should equal 'tytylXTteheFXxMMoxruuKBnzu'

As I understood it:

TyTYLX  => TyTYLX 
TtEheF  => TtEheF
xXm     => XXM
MOXruUK => MOXruUK
bNZU    => BNZU

TyTYLXTtEheFXXMMOXruUKBNZU => tyTYLXTtEheFXXMMOXruUKBNZu